1
|
Nicholson JG, Cirigliano S, Singhania R, Haywood C, Shahidi Dadras M, Yoshimura M, Vanderbilt D, Liechty B, Fine HA. Chronic hypoxia remodels the tumor microenvironment to support glioma stem cell growth. Acta Neuropathol Commun 2024; 12:46. [PMID: 38528608 DOI: 10.1186/s40478-024-01755-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/05/2024] [Indexed: 03/27/2024] Open
Abstract
Cerebral organoids co-cultured with patient derived glioma stem cells (GLICOs) are an experimentally tractable research tool useful for investigating the role of the human brain tumor microenvironment in glioblastoma. Here we describe long-term GLICOs, a novel model in which COs are grown from embryonic stem cell cultures containing low levels of GSCs and tumor development is monitored over extended durations (ltGLICOs). Single-cell profiling of ltGLICOs revealed an unexpectedly long latency period prior to GSC expansion, and that normal organoid development was unimpaired by the presence of low numbers of GSCs. However, as organoids age they experience chronic hypoxia and oxidative stress which remodels the tumor microenvironment to promote GSC expansion. Receptor-ligand modelling identified astrocytes, which secreted various pro-tumorigenic ligands including FGF1, as the primary cell type for GSC crosstalk and single-cell multi-omic analysis revealed these astrocytes were under the control of ischemic regulatory networks. Functional validation confirmed hypoxia as a driver of pro-tumorigenic astrocytic ligand secretion and that GSC expansion was accelerated by pharmacological induction of oxidative stress. When controlled for genotype, the close association between glioma aggressiveness and patient age has very few proposed biological explanations. Our findings indicate that age-associated increases in cerebral vascular insufficiency and associated regional chronic cerebral hypoxia may contribute to this phenomenon.
Collapse
Affiliation(s)
- J G Nicholson
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - S Cirigliano
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - R Singhania
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - C Haywood
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - M Shahidi Dadras
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - M Yoshimura
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - D Vanderbilt
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA
| | - B Liechty
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine/New York-Presbyterian Hospital, New York, NY, USA
| | - H A Fine
- Department of Neurology, Weill Cornell Medicine, New York, NY, USA.
| |
Collapse
|
2
|
Lim S, Singh S, Huang FT, Pan S, Wang K, Kim J, Kim J, Vanderbilt D, Cheong SW. Magnetochiral tunneling in paramagnetic Co 1/3NbS 2. Proc Natl Acad Sci U S A 2024; 121:e2318443121. [PMID: 38412131 DOI: 10.1073/pnas.2318443121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 01/25/2024] [Indexed: 02/29/2024] Open
Abstract
Electric currents have the intriguing ability to induce magnetization in nonmagnetic crystals with sufficiently low crystallographic symmetry. Some associated phenomena include the non-linear anomalous Hall effect in polar crystals and the nonreciprocal directional dichroism in chiral crystals when magnetic fields are applied. In this work, we demonstrate that the same underlying physics is also manifested in the electronic tunneling process between the surface of a nonmagnetic chiral material and a magnetized scanning probe. In the paramagnetic but chiral metallic compound Co1/3NbS2, the magnetization induced by the tunneling current is shown to become detectable by its coupling to the magnetization of the tip itself. This results in a contrast across different chiral domains, achieving atomic-scale spatial resolution of structural chirality. To support the proposed mechanism, we used first-principles theory to compute the chirality-dependent current-induced magnetization and Berry curvature in the bulk of the material. Our demonstration of this magnetochiral tunneling effect opens up an avenue for investigating atomic-scale variations in the local crystallographic symmetry and electronic structure across the structural domain boundaries of low-symmetry nonmagnetic crystals.
Collapse
Affiliation(s)
- Seongjoon Lim
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Sobhit Singh
- Department of Mechanical Engineering, University of Rochester, Rochester, NY 14627
- Materials Science Program, University of Rochester, Rochester, NY 14627
| | - Fei-Ting Huang
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Shangke Pan
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
- State Key Laboratory Base of Novel Function Materials and Preparation Science, School of Material Sciences and Chemical Engineering, Ningbo University, Ningbo 315211, China
| | - Kefeng Wang
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Jaewook Kim
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Sang-Wook Cheong
- Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| |
Collapse
|
3
|
Musfeldt JL, Singh S, Fan S, Gu Y, Xu X, Cheong SW, Liu Z, Vanderbilt D, Rabe KM. Structural phase purification of bulk HfO 2:Y through pressure cycling. Proc Natl Acad Sci U S A 2024; 121:e2312571121. [PMID: 38266049 PMCID: PMC10835063 DOI: 10.1073/pnas.2312571121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 12/05/2023] [Indexed: 01/26/2024] Open
Abstract
We combine synchrotron-based infrared absorption and Raman scattering spectroscopies with diamond anvil cell techniques and first-principles calculations to explore the properties of hafnia under compression. We find that pressure drives HfO[Formula: see text]:7%Y from the mixed monoclinic ([Formula: see text]) [Formula: see text] antipolar orthorhombic ([Formula: see text]) phase to pure antipolar orthorhombic ([Formula: see text]) phase at approximately 6.3 GPa. This transformation is irreversible, meaning that upon release, the material is kinetically trapped in the [Formula: see text] metastable state at 300 K. Compression also drives polar orthorhombic ([Formula: see text]) hafnia into the tetragonal ([Formula: see text]) phase, although the latter is not metastable upon release. These results are unified by an analysis of the energy landscape. The fact that pressure allows us to stabilize targeted metastable structures with less Y stabilizer is important to preserving the flat phonon band physics of pure HfO[Formula: see text].
Collapse
Affiliation(s)
- J L Musfeldt
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
- Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996
| | - Sobhit Singh
- Department of Mechanical Engineering, University of Rochester, Rochester, NY 14627
- Materials Science Program, University of Rochester, Rochester, NY 14627
| | - Shiyu Fan
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973
| | - Yanhong Gu
- Department of Chemistry, University of Tennessee, Knoxville, TN 37996
| | - Xianghan Xu
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ 08854
| | - S-W Cheong
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, NJ 08854
| | - Z Liu
- Department of Physics, University of Illinois, Chicago, IL 60607-7059
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854
| |
Collapse
|
4
|
Berry T, Varnava N, Ryan DH, Stewart VJ, Rasta R, Heinmaa I, Kumar N, Schnelle W, Bhandia R, Pasco CM, Armitage NP, Stern R, Felser C, Vanderbilt D, McQueen TM. Bonding and Suppression of a Magnetic Phase Transition in EuMn 2P 2. J Am Chem Soc 2023; 145:4527-4533. [PMID: 36789888 DOI: 10.1021/jacs.2c11324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Electrons in solids often adopt complex patterns of chemical bonding driven by the competition between energy gains from covalency and delocalization, and energy costs of double occupation to satisfy Pauli exclusion, with multiple intermediate states in the transition between highly localized, and magnetic, and delocalized, and nonmagnetic limits. Herein, we report a chemical pressure-driven transition from a proper Mn magnetic ordering phase transition to a Mn magnetic phase crossover in EuMn2P2 the limiting end member of the EuMn2X2 (X = Sb, As, P) family of layered materials. This loss of a magnetic ordering occurs despite EuMn2P2 remaining an insulator at all temperatures, and with a phase transition to long-range Eu antiferromagnetic order at TN ≈ 17 K. The absence of a Mn magnetic phase transition contrasts with the formation of long-range Mn order at T ≈ 130 K in isoelectronic EuMn2Sb2 and EuMn2As2. Temperature-dependent specific heat and 31P NMR measurements provide evidence for the development of short-range Mn magnetic correlations from T ≈ 250-100 K, interpreted as a precursor to covalent bond formation. Density functional theory calculations demonstrate an unusual sensitivity of the band structure to the details of the imposed Mn and Eu magnetic order, with an antiferromagnetic Mn arrangement required to recapitulate an insulating state. Our results imply a picture in which long-range Mn magnetic order is suppressed by chemical pressure, but that antiferromagnetic correlations persist, narrowing bands and producing an insulating state.
Collapse
Affiliation(s)
- Tanya Berry
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Department of Chemistry, Princeton University, Princeton, New Jersey 08540, United States
| | - Nicodemos Varnava
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Dominic H Ryan
- Physics Department and Centre for the Physics of Materials, McGill University, 3600 University Street, Montreal, Quebec H3A 2T8, Canada
| | - Veronica J Stewart
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Riho Rasta
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Ivo Heinmaa
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Nitesh Kumar
- Max-Planck-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Walter Schnelle
- Max-Planck-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - Rishi Bhandia
- Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Christopher M Pasco
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - N P Armitage
- Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Raivo Stern
- National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, 12618 Tallinn, Estonia
| | - Claudia Felser
- Max-Planck-Institute for Chemical Physics of Solids, D-01187 Dresden, Germany
| | - David Vanderbilt
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Tyrel M McQueen
- Department of Chemistry, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Institute for Quantum Matter, William H. Miller III Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, United States.,Department of Materials Science and Engineering, The Johns Hopkins University, Baltimore, Maryland 21218, United States
| |
Collapse
|
5
|
Bonini J, Ren S, Vanderbilt D, Stengel M, Dreyer CE, Coh S. Frequency Splitting of Chiral Phonons from Broken Time-Reversal Symmetry in CrI_{3}. Phys Rev Lett 2023; 130:086701. [PMID: 36898102 DOI: 10.1103/physrevlett.130.086701] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/19/2023] [Indexed: 06/18/2023]
Abstract
Conventional approaches for lattice dynamics based on static interatomic forces do not fully account for the effects of time-reversal-symmetry breaking in magnetic systems. Recent approaches to rectify this involve incorporating the first-order change in forces with atomic velocities under the assumption of adiabatic separation of electronic and nuclear degrees of freedom. In this Letter, we develop a first-principles method to calculate this velocity-force coupling in extended solids and show via the example of ferromagnetic CrI_{3} that, due to the slow dynamics of the spins in the system, the assumption of adiabatic separation can result in large errors for splittings of zone-center chiral modes. We demonstrate that an accurate description of the lattice dynamics requires treating magnons and phonons on the same footing.
Collapse
Affiliation(s)
- John Bonini
- Center for Computational Quantum Physics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, USA
| | - Shang Ren
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08845-0849, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08845-0849, USA
| | - Massimiliano Stengel
- Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus UAB, 08193 Bellaterra, Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
| | - Cyrus E Dreyer
- Center for Computational Quantum Physics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, USA
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800, USA
| | - Sinisa Coh
- Materials Science and Mechanical Engineering, University of California, Riverside, California 92521, USA
| |
Collapse
|
6
|
Ge W, Kim J, Chan YT, Vanderbilt D, Yan J, Wu W. Direct Visualization of Surface Spin-Flip Transition in MnBi_{4}Te_{7}. Phys Rev Lett 2022; 129:107204. [PMID: 36112444 DOI: 10.1103/physrevlett.129.107204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 06/23/2022] [Accepted: 08/09/2022] [Indexed: 06/15/2023]
Abstract
We report direct visualization of spin-flip transition of the surface layer in antiferromagnet MnBi_{4}Te_{7}, a natural superlattice of alternating MnBi_{2}Te_{4} and Bi_{2}Te_{3} layers, using cryogenic magnetic force microscopy (MFM). The observation of magnetic contrast across domain walls and step edges confirms that the antiferromagnetic order persists to the surface layers. The magnetic field dependence of the MFM images reveals that the surface magnetic layer undergoes a first-order spin-flip transition at a magnetic field that is lower than the bulk transition, in excellent agreement with a revised Mills model. Our analysis suggests no reduction of the order parameter in the surface magnetic layer, implying robust ferromagnetism in the single-layer limit. The direct visualization of surface spin-flip transition not only opens up exploration of surface metamagnetic transitions in layered antiferromagnets, but also provides experimental support for realizing quantized transport in ultrathin films of MnBi_{4}Te_{7} and other natural superlattice topological magnets.
Collapse
Affiliation(s)
- Wenbo Ge
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Ying-Ting Chan
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Weida Wu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
7
|
Gaudet J, Yang HY, Baidya S, Lu B, Xu G, Zhao Y, Rodriguez-Rivera JA, Hoffmann CM, Graf DE, Torchinsky DH, Nikolić P, Vanderbilt D, Tafti F, Broholm CL. Weyl-mediated helical magnetism in NdAlSi. Nat Mater 2021; 20:1650-1656. [PMID: 34413490 DOI: 10.1038/s41563-021-01062-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
Emergent relativistic quasiparticles in Weyl semimetals are the source of exotic electronic properties such as surface Fermi arcs, the anomalous Hall effect and negative magnetoresistance, all observed in real materials. Whereas these phenomena highlight the effect of Weyl fermions on the electronic transport properties, less is known about what collective phenomena they may support. Here, we report a Weyl semimetal, NdAlSi, that offers an example. Using neutron diffraction, we found a long-wavelength helical magnetic order in NdAlSi, the periodicity of which is linked to the nesting vector between two topologically non-trivial Fermi pockets, which we characterize using density functional theory and quantum oscillation measurements. We further show the chiral transverse component of the spin structure is promoted by bond-oriented Dzyaloshinskii-Moriya interactions associated with Weyl exchange processes. Our work provides a rare example of Weyl fermions driving collective magnetism.
Collapse
Affiliation(s)
- Jonathan Gaudet
- Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University, Baltimore, MD, USA.
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA.
- Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA.
| | - Hung-Yu Yang
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Santu Baidya
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA
| | - Baozhu Lu
- Department of Physics, Temple University, Philadelphia, PA, USA
| | - Guangyong Xu
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - Yang Zhao
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA
| | - Jose A Rodriguez-Rivera
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
- Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA
| | | | - David E Graf
- National High Magnetic Field Laboratory, Tallahassee, FL, USA
| | | | - Predrag Nikolić
- Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University, Baltimore, MD, USA
- Department of Physics and Astronomy, George Mason University, Fairfax, VA, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA
| | - Fazel Tafti
- Department of Physics, Boston College, Chestnut Hill, MA, USA
| | - Collin L Broholm
- Department of Physics and Astronomy and Institute for Quantum Matter, The Johns Hopkins University, Baltimore, MD, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, USA
| |
Collapse
|
8
|
Varnava N, Wilson JH, Pixley JH, Vanderbilt D. Controllable quantum point junction on the surface of an antiferromagnetic topological insulator. Nat Commun 2021; 12:3998. [PMID: 34183668 PMCID: PMC8238970 DOI: 10.1038/s41467-021-24276-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 05/31/2021] [Indexed: 11/08/2022] Open
Abstract
Engineering and manipulation of unidirectional channels has been achieved in quantum Hall systems, leading to the construction of electron interferometers and proposals for low-power electronics and quantum information science applications. However, to fully control the mixing and interference of edge-state wave functions, one needs stable and tunable junctions. Encouraged by recent material candidates, here we propose to achieve this using an antiferromagnetic topological insulator that supports two distinct types of gapless unidirectional channels, one from antiferromagnetic domain walls and the other from single-height steps. Their distinct geometric nature allows them to intersect robustly to form quantum point junctions, which then enables their control by magnetic and electrostatic local probes. We show how the existence of stable and tunable junctions, the intrinsic magnetism and the potential for higher-temperature performance make antiferromagnetic topological insulators a promising platform for electron quantum optics and microelectronic applications.
Collapse
Affiliation(s)
- Nicodemos Varnava
- Department of Physics & Astronomy, Center for Materials Theory, Rutgers University, Piscataway, NJ, USA.
| | - Justin H Wilson
- Department of Physics & Astronomy, Center for Materials Theory, Rutgers University, Piscataway, NJ, USA
| | - J H Pixley
- Department of Physics & Astronomy, Center for Materials Theory, Rutgers University, Piscataway, NJ, USA
- Center for Computational Quantum Physics, Flatiron Institute, New York, NY, USA
- Physics Department, Princeton University, Princeton, NJ, USA
| | - David Vanderbilt
- Department of Physics & Astronomy, Center for Materials Theory, Rutgers University, Piscataway, NJ, USA
| |
Collapse
|
9
|
Liu X, Singh S, Drouin-Touchette V, Asaba T, Brewer J, Zhang Q, Cao Y, Pal B, Middey S, Kumar PSA, Kareev M, Gu L, Sarma DD, Shafer P, Arenholz E, Freeland JW, Li L, Vanderbilt D, Chakhalian J. Proximate Quantum Spin Liquid on Designer Lattice. Nano Lett 2021; 21:2010-2017. [PMID: 33617255 DOI: 10.1021/acs.nanolett.0c04498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Complementary to bulk synthesis, here we propose a designer lattice with extremely high magnetic frustration and demonstrate the possible realization of a quantum spin liquid state from both experiments and theoretical calculations. In an ultrathin (111) CoCr2O4 slice composed of three triangular and one kagome cation planes, the absence of a spin ordering or freezing transition is demonstrated down to 0.03 K, in the presence of strong antiferromagnetic correlations in the energy scale of 30 K between Co and Cr sublattices, leading to the frustration factor of ∼1000. Persisting spin fluctuations are observed at low temperatures via low-energy muon spin relaxation. Our calculations further demonstrate the emergence of highly degenerate magnetic ground states at the 0 K limit, due to the competition among multiply altered exchange interactions. These results collectively indicate the realization of a proximate quantum spin liquid state on the synthetic lattice.
Collapse
Affiliation(s)
- Xiaoran Liu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Sobhit Singh
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Victor Drouin-Touchette
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Tomoya Asaba
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Jess Brewer
- TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2A3
- Department of Physics and Astronomy, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z1
| | - Qinghua Zhang
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P.R. China
| | - Yanwei Cao
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo, Zhejiang 315201, China
| | - Banabir Pal
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru 560012, India
| | - Srimanta Middey
- Department of Physics, Indian Institute of Science, Bengaluru 560012, India
| | - P S Anil Kumar
- Department of Physics, Indian Institute of Science, Bengaluru 560012, India
| | - Mikhail Kareev
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Lin Gu
- Beijing National Laboratory for Condensed-Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P.R. China
| | - D D Sarma
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bengaluru 560012, India
| | - Padraic Shafer
- Advanced Light Source, Lawrence Berkley National Laboratory, Berkeley, California 94720, United States
| | - Elke Arenholz
- Advanced Light Source, Lawrence Berkley National Laboratory, Berkeley, California 94720, United States
| | - John W Freeland
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Lu Li
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Jak Chakhalian
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, United States
| |
Collapse
|
10
|
Singh S, Kim J, Rabe KM, Vanderbilt D. Engineering Weyl Phases and Nonlinear Hall Effects in T_{d}-MoTe_{2}. Phys Rev Lett 2020; 125:046402. [PMID: 32794815 DOI: 10.1103/physrevlett.125.046402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 07/09/2020] [Accepted: 06/23/2020] [Indexed: 06/11/2023]
Abstract
MoTe_{2} has recently attracted much attention due to the observation of pressure-induced superconductivity, exotic topological phase transitions, and nonlinear quantum effects. However, there has been debate on the intriguing structural phase transitions among various observed phases of MoTe_{2} and their connection to the underlying topological electronic properties. In this work, by means of density-functional theory calculations, we investigate the structural phase transition between the polar T_{d} and nonpolar 1T^{'} phases of MoTe_{2} in reference to a hypothetical high-symmetry T_{0} phase that exhibits higher-order topological features. In the T_{d} phase we obtain a total of 12 Weyl points, which can be created/annihilated, dynamically manipulated, and switched by tuning a polar phonon mode. We also report the existence of a tunable nonlinear Hall effect in T_{d}-MoTe_{2} and propose the use of this effect as a probe for the detection of polarity orientation in polar (semi)metals. By studying the role of dimensionality, we identify a configuration in which a nonlinear surface response current emerges. The potential technological applications of the tunable Weyl phase and the nonlinear Hall effect are discussed.
Collapse
Affiliation(s)
- Sobhit Singh
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
11
|
Sass PM, Kim J, Vanderbilt D, Yan J, Wu W. Robust A-Type Order and Spin-Flop Transition on the Surface of the Antiferromagnetic Topological Insulator MnBi_{2}Te_{4}. Phys Rev Lett 2020; 125:037201. [PMID: 32745385 DOI: 10.1103/physrevlett.125.037201] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Accepted: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Here, we present microscopic evidence of the persistence of uniaxial A-type antiferromagnetic order to the surface layers of MnBi_{2}Te_{4} single crystals using magnetic force microscopy. Our results reveal termination-dependent magnetic contrast across both surface step edges and domain walls, which can be screened by thin layers of soft magnetism. The robust surface A-type order is further corroborated by the observation of termination-dependent surface spin-flop transitions, which have been theoretically proposed decades ago. Our results not only provide key ingredients for understanding the electronic properties of the antiferromagnetic topological insulator MnBi_{2}Te_{4}, but also open a new paradigm for exploring intrinsic surface metamagnetic transitions in natural antiferromagnets.
Collapse
Affiliation(s)
- Paul M Sass
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Jiaqiang Yan
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Weida Wu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
12
|
Pizzi G, Vitale V, Arita R, Blügel S, Freimuth F, Géranton G, Gibertini M, Gresch D, Johnson C, Koretsune T, Ibañez-Azpiroz J, Lee H, Lihm JM, Marchand D, Marrazzo A, Mokrousov Y, Mustafa JI, Nohara Y, Nomura Y, Paulatto L, Poncé S, Ponweiser T, Qiao J, Thöle F, Tsirkin SS, Wierzbowska M, Marzari N, Vanderbilt D, Souza I, Mostofi AA, Yates JR. Wannier90 as a community code: new features and applications. J Phys Condens Matter 2020; 32:165902. [PMID: 31658458 DOI: 10.1088/1361-648x/ab51ff] [Citation(s) in RCA: 215] [Impact Index Per Article: 53.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Wannier90 is an open-source computer program for calculating maximally-localised Wannier functions (MLWFs) from a set of Bloch states. It is interfaced to many widely used electronic-structure codes thanks to its independence from the basis sets representing these Bloch states. In the past few years the development of Wannier90 has transitioned to a community-driven model; this has resulted in a number of new developments that have been recently released in Wannier90 v3.0. In this article we describe these new functionalities, that include the implementation of new features for wannierisation and disentanglement (symmetry-adapted Wannier functions, selectively-localised Wannier functions, selected columns of the density matrix) and the ability to calculate new properties (shift currents and Berry-curvature dipole, and a new interface to many-body perturbation theory); performance improvements, including parallelisation of the core code; enhancements in functionality (support for spinor-valued Wannier functions, more accurate methods to interpolate quantities in the Brillouin zone); improved usability (improved plotting routines, integration with high-throughput automation frameworks), as well as the implementation of modern software engineering practices (unit testing, continuous integration, and automatic source-code documentation). These new features, capabilities, and code development model aim to further sustain and expand the community uptake and range of applicability, that nowadays spans complex and accurate dielectric, electronic, magnetic, optical, topological and transport properties of materials.
Collapse
Affiliation(s)
- Giovanni Pizzi
- Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Liu X, Singh S, Kirby BJ, Zhong Z, Cao Y, Pal B, Kareev M, Middey S, Freeland JW, Shafer P, Arenholz E, Vanderbilt D, Chakhalian J. Emergent Magnetic State in (111)-Oriented Quasi-Two-Dimensional Spinel Oxides. Nano Lett 2019; 19:8381-8387. [PMID: 31665887 DOI: 10.1021/acs.nanolett.9b02159] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report on the emergent magnetic state of (111)-oriented CoCr2O4 ultrathin films sandwiched between Al2O3 spacer layers in a quantum confined geometry. At the two-dimensional crossover, polarized neutron reflectometry reveals an anomalous enhancement of the total magnetization compared to the bulk value. Synchrotron X-ray magnetic circular dichroism measurements demonstrate the appearance of a long-range ferromagnetic ordering of spins on both Co and Cr sublattices. Brillouin function analyses and ab-initio density functional theory calculations further corroborate that the observed phenomena are due to the strongly altered magnetic frustration invoked by quantum confinement effects, manifested by the onset of a Yafet-Kittel-type ordering as the magnetic ground state in the ultrathin limit, which is unattainable in the bulk.
Collapse
Affiliation(s)
- Xiaoran Liu
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Sobhit Singh
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Brian J Kirby
- NIST Center for Neutron Research , National Institute of Standards and Technology , Gaithersburg , Maryland 20899 , United States
| | - Zhicheng Zhong
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences , Ningbo , Zhejiang 315201 , China
| | - Yanwei Cao
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences , Ningbo , Zhejiang 315201 , China
| | - Banabir Pal
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Mikhail Kareev
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Srimanta Middey
- Department of Physics , Indian Institute of Science , Bengaluru 560012 , India
| | - John W Freeland
- Advanced Photon Source , Argonne National Laboratory , Argonne , Illinois 60439 , United States
| | - Padraic Shafer
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - Elke Arenholz
- Advanced Light Source , Lawrence Berkeley National Laboratory , Berkeley , California 94720 , United States
| | - David Vanderbilt
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| | - Jak Chakhalian
- Department of Physics and Astronomy , Rutgers University , Piscataway , New Jersey 08854 , United States
| |
Collapse
|
14
|
Kim HS, Haule K, Vanderbilt D. Mott Metal-Insulator Transitions in Pressurized Layered Trichalcogenides. Phys Rev Lett 2019; 123:236401. [PMID: 31868467 DOI: 10.1103/physrevlett.123.236401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 09/17/2019] [Indexed: 06/10/2023]
Abstract
Transition metal phosphorous trichalcogenides, MPX_{3} (M and X being transition metal and chalcogen elements, respectively), have been the focus of substantial interest recently because they are unusual candidates undergoing Mott transition in the two-dimensional limit. Here we investigate material properties of the compounds with M=Mn and Ni employing ab initio density functional and dynamical mean-field calculations, especially their electronic behavior under external pressure in the paramagnetic phase. Mott metal-insulator transitions (MIT) are found to be a common feature for both compounds, but their lattice structures show drastically different behaviors depending on the relevant orbital degrees of freedom, i.e., t_{2g} or e_{g}. Under pressure, MnPS_{3} can undergo an isosymmetric structural transition within monoclinic space group by forming Mn-Mn dimers due to the strong direct overlap between the neighboring t_{2g} orbitals, accompanied by a significant volume collapse and a spin-state transition. In contrast, NiPS_{3} and NiPSe_{3}, with their active e_{g} orbital degrees of freedom, do not show a structural change at the MIT pressure or deep in the metallic phase within the monoclinic symmetry. Hence NiPS_{3} and NiPSe_{3} become rare examples of materials hosting electronic bandwidth-controlled Mott MITs, thus showing promise for ultrafast resistivity switching behavior.
Collapse
Affiliation(s)
- Heung-Sik Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
- Department of Physics, Kangwon National University, Chuncheon 24341, Korea
| | - Kristjan Haule
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
15
|
Huang FT, Joon Lim S, Singh S, Kim J, Zhang L, Kim JW, Chu MW, Rabe KM, Vanderbilt D, Cheong SW. Polar and phase domain walls with conducting interfacial states in a Weyl semimetal MoTe 2. Nat Commun 2019; 10:4211. [PMID: 31527602 PMCID: PMC6746811 DOI: 10.1038/s41467-019-11949-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 08/13/2019] [Indexed: 11/09/2022] Open
Abstract
Much of the dramatic growth in research on topological materials has focused on topologically protected surface states. While the domain walls of topological materials such as Weyl semimetals with broken inversion or time-reversal symmetry can provide a hunting ground for exploring topological interfacial states, such investigations have received little attention to date. Here, utilizing in-situ cryogenic transmission electron microscopy combined with first-principles calculations, we discover intriguing domain-wall structures in MoTe2, both between polar variants of the low-temperature(T) Weyl phase, and between this and the high-T higher-order topological phase. We demonstrate how polar domain walls can be manipulated with electron beams and show that phase domain walls tend to form superlattice-like structures along the c axis. Scanning tunneling microscopy indicates a possible signature of a conducting hinge state at phase domain walls. Our results open avenues for investigating topological interfacial states and unveiling multifunctional aspects of domain walls in topological materials.
Collapse
Affiliation(s)
- Fei-Ting Huang
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Seong Joon Lim
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Sobhit Singh
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Jinwoong Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Lunyong Zhang
- Laboratory for Pohang Emergent Materials and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Jae-Wook Kim
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Ming-Wen Chu
- Center for Condensed Matter Sciences and Center of Atomic Initiative for New Materials, National Taiwan University, 106, Taipei, Taiwan
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA
| | - Sang-Wook Cheong
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, 08854, USA.
| |
Collapse
|
16
|
Jiang Z, Paillard C, Vanderbilt D, Xiang H, Bellaiche L. Designing Multifunctionality via Assembling Dissimilar Materials: Epitaxial AlN/ScN Superlattices. Phys Rev Lett 2019; 123:096801. [PMID: 31524461 DOI: 10.1103/physrevlett.123.096801] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Indexed: 06/10/2023]
Abstract
First-principles calculations are performed to investigate the effect of epitaxial strain on energetic, structural, electrical, electronic, and optical properties of 1×1 AlN/ScN superlattices. This system is predicted to adopt four different strain regions exhibiting different properties, including optimization of various physical responses such as piezoelectricity, electro-optic and elasto-optic coefficients, and elasticity. Varying the strain between these four different regions also allows the creation of an electrical polarization in a nominally paraelectric material, as a result of a softening of the lowest optical mode, and even the control of its magnitude up to a giant value. Furthermore, it results in an electronic band gap that cannot only change its nature (direct vs indirect), but also cover a wide range of the electromagnetic spectrum from the blue, through the violet and near ultraviolet, to the middle ultraviolet. These findings thus point out the potential of assembling two different materials inside the same heterostructure to design multifunctionality and striking phenomena.
Collapse
Affiliation(s)
- Zhijun Jiang
- Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
- School of Physics and Optoelectronic Engineering, Ludong University, Yantai 264025, China
| | - Charles Paillard
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
- Laboratoire SPMS, CentraleSupélec/CNRS UMR 8580, Université Paris-Saclay, 8-10 rue Joliot Curie, 91190 Gif-sur-Yvette, France
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Hongjun Xiang
- Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433, China
- Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - L Bellaiche
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA
| |
Collapse
|
17
|
Moon J, Kim J, Koirala N, Salehi M, Vanderbilt D, Oh S. Ferromagnetic Anomalous Hall Effect in Cr-Doped Bi 2Se 3 Thin Films via Surface-State Engineering. Nano Lett 2019; 19:3409-3414. [PMID: 31038971 DOI: 10.1021/acs.nanolett.8b03745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The anomalous Hall effect (AHE) is a nonlinear Hall effect appearing in magnetic conductors, boosted by internal magnetism beyond what is expected from the ordinary Hall effect. With the recent discovery of the quantized version of the AHE, the quantum anomalous Hall effect (QAHE), in Cr- or V-doped topological insulator (TI) (Sb,Bi)2Te3 thin films, the AHE in magnetic TIs has been attracting significant interest. However, one of the puzzles in this system has been that while Cr- or V-doped (Sb,Bi)2Te3 and V-doped Bi2Se3 exhibit AHE, Cr-doped Bi2Se3 has failed to exhibit even ferromagnetic AHE, the expected predecessor to the QAHE, though it is the first material predicted to exhibit the QAHE. Here, we have successfully implemented ferromagnetic AHE in Cr-doped Bi2Se3 thin films by utilizing a surface state engineering scheme. Surprisingly, the observed ferromagnetic AHE in the Cr-doped Bi2Se3 thin films exhibited only a positive slope regardless of the carrier type. We show that this sign problem can be explained by the intrinsic Berry curvature of the system as calculated from a tight-binding model combined with a first-principles method.
Collapse
Affiliation(s)
- Jisoo Moon
- Department of Physics and Astronomy , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| | - Jinwoong Kim
- Department of Physics and Astronomy , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| | - Nikesh Koirala
- Department of Physics and Astronomy , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| | - Maryam Salehi
- Department of Materials Science and Engineering , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| | - David Vanderbilt
- Department of Physics and Astronomy , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| | - Seongshik Oh
- Department of Physics and Astronomy , Rutgers, The State University of New Jersey , Piscataway , New Jersey 08854 , United States
| |
Collapse
|
18
|
Gong C, Xie Y, Chen Y, Kim HS, Vanderbilt D. Symmorphic Intersecting Nodal Rings in Semiconducting Layers. Phys Rev Lett 2018; 120:106403. [PMID: 29570330 DOI: 10.1103/physrevlett.120.106403] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 01/23/2018] [Indexed: 06/08/2023]
Abstract
The unique properties of topological semimetals have strongly driven efforts to seek for new topological phases and related materials. Here, we identify a critical condition for the existence of intersecting nodal rings (INRs) in symmorphic crystals, and further classify all possible kinds of INRs which can be obtained in the layered semiconductors with Amm2 and Cmmm space group symmetries. Several honeycomb structures are suggested to be topological INR semimetals, including layered and "hidden" layered structures. Transitions between the three types of INRs, named as α, β, and γ type, can be driven by external strains in these structures. The resulting surface states and Landau-level structures, more complicated than those resulting from a simple nodal loop, are also discussed.
Collapse
Affiliation(s)
- Cheng Gong
- School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Yuee Xie
- School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Yuanping Chen
- School of Physics and Optoelectronics, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Heung-Sik Kim
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
19
|
Monserrat B, Bennett JW, Rabe KM, Vanderbilt D. Antiferroelectric Topological Insulators in Orthorhombic AMgBi Compounds (A=Li, Na, K). Phys Rev Lett 2017; 119:036802. [PMID: 28777633 DOI: 10.1103/physrevlett.119.036802] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Indexed: 06/07/2023]
Abstract
We introduce antiferroelectric topological insulators as a new class of functional materials in which an electric field can be used to control topological order and induce topological phase transitions. Using first principles methods, we predict that several alkali-MgBi orthorhombic members of an ABC family of compounds are antiferroelectric topological insulators. We also show that epitaxial strain and hydrostatic pressure can be used to tune the topological order and the band gap of these ABC compounds. Antiferroelectric topological insulators could enable precise control of topology using electric fields, enhancing the applicability of topological materials in electronics and spintronics.
Collapse
Affiliation(s)
- Bartomeu Monserrat
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
- TCM Group, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Joseph W Bennett
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
20
|
Zhang H, Haule K, Vanderbilt D. Metal-Insulator Transition and Topological Properties of Pyrochlore Iridates. Phys Rev Lett 2017; 118:026404. [PMID: 28128605 DOI: 10.1103/physrevlett.118.026404] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Indexed: 06/06/2023]
Abstract
Combining density functional theory (DFT) and embedded dynamical mean-field theory (DMFT) methods, we study the metal-insulator transition in R_{2}Ir_{2}O_{7} (R=Y, Eu, Sm, Nd, Pr, and Bi) and the topological nature of the insulating compounds. Accurate free energies evaluated using the charge self-consistent DFT+DMFT method reveal that the metal-insulator transition occurs for an A-cation radius between that of Nd and Pr, in agreement with experiments. The all-in-all-out magnetic phase, which is stable in the Nd compound but not the Pr one, gives rise to a small Ir^{4+} magnetic moment of ≈0.4 μ_{B} and opens a sizable correlated gap. We demonstrate that within this state-of-the-art theoretical method, the insulating bulk pyrochlore iridates are topologically trivial.
Collapse
Affiliation(s)
- Hongbin Zhang
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Kristjan Haule
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
21
|
Liu J, Park SY, Garrity KF, Vanderbilt D. Flux States and Topological Phases from Spontaneous Time-Reversal Symmetry Breaking in CrSi(Ge)Te_{3}-Based Systems. Phys Rev Lett 2016; 117:257201. [PMID: 28036224 DOI: 10.1103/physrevlett.117.257201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Indexed: 06/06/2023]
Abstract
We study adatom-covered single layers of CrSiTe_{3} and CrGeTe_{3} using first-principles calculations based on hybrid functionals. We find that the insulating ground state of a monolayer of La (Lu) deposited on single-layer CrSiTe_{3} (CrGeTe_{3}) carries spontaneously generated current loops around the Cr sites. These "flux states" induce antiferromagnetically ordered orbital moments on the Cr sites and are also associated with nontrivial topological properties. The calculated Chern numbers for these systems are predicted to be ±1 even in the absence of spin-orbit coupling, with sizable gaps on the order of 100 meV. The flux states and the associated topological phases result from spontaneous time-reversal symmetry breaking due to the presence of nonlocal Coulomb interactions.
Collapse
Affiliation(s)
- Jianpeng Liu
- Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - Se Young Park
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | - Kevin F Garrity
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
22
|
Abstract
We study the effects of temperature on the band structure of the Bi_{2}Se_{3} family of topological insulators using first-principles methods. Increasing temperature drives these materials towards the normal state, with similar contributions from thermal expansion and from electron-phonon coupling. The band gap changes with temperature reach 0.3 eV at 600 K, of similar size to the changes caused by electron correlation. Our results suggest that temperature-induced topological phase transitions should be observable near critical points of other external parameters.
Collapse
Affiliation(s)
- Bartomeu Monserrat
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
- TCM Group, Cavendish Laboratory, University of Cambridge, J. J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| |
Collapse
|
23
|
Yokosuk MO, Al-Wahish A, Artyukhin S, O'Neal KR, Mazumdar D, Chen P, Yang J, Oh YS, McGill SA, Haule K, Cheong SW, Vanderbilt D, Musfeldt JL. Magnetoelectric Coupling through the Spin Flop Transition in Ni_{3}TeO_{6}. Phys Rev Lett 2016; 117:147402. [PMID: 27740819 DOI: 10.1103/physrevlett.117.147402] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Indexed: 06/06/2023]
Abstract
We combined high field optical spectroscopy and first principles calculations to analyze the electronic structure of Ni_{3}TeO_{6} across the 53 K and 9 T magnetic transitions, both of which are accompanied by large changes in electric polarization. The color properties are sensitive to magnetic order due to field-induced changes in the crystal field environment, with those around Ni1 and Ni2 most affected. These findings advance the understanding of magnetoelectric coupling in materials in which magnetic 3d centers coexist with nonmagnetic heavy chalcogenide cations.
Collapse
Affiliation(s)
- M O Yokosuk
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Amal Al-Wahish
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Sergey Artyukhin
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Quantum Materials Theory, Italian Institute of Technology, Via Morego 30, 16163 Genova, Italy
| | - K R O'Neal
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - D Mazumdar
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - P Chen
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - Junjie Yang
- Laboratory for Pohang Emergent Materials and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
| | - Yoon Seok Oh
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Stephen A McGill
- National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32310, USA
| | - K Haule
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Sang-Wook Cheong
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
- Laboratory for Pohang Emergent Materials and Max Plank POSTECH Center for Complex Phase Materials, Pohang University of Science and Technology, Pohang 790-784, Korea
- Rutgers Center for Emergent Materials, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - J L Musfeldt
- Department of Chemistry, University of Tennessee, Knoxville, Tennessee 37996, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| |
Collapse
|
24
|
Di Sante D, Barone P, Stroppa A, Garrity KF, Vanderbilt D, Picozzi S. Intertwined Rashba, Dirac, and Weyl Fermions in Hexagonal Hyperferroelectrics. Phys Rev Lett 2016; 117:076401. [PMID: 27563977 DOI: 10.1103/physrevlett.117.076401] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Indexed: 06/06/2023]
Abstract
By means of density functional theory based calculations, we study the role of spin-orbit coupling in the new family of ABC hyperferroelectrics [Garrity, Rabe, and Vanderbilt Phys. Rev. Lett. 112, 127601 (2014)]. We unveil an extremely rich physics strongly linked to ferroelectric properties, ranging from the electric control of bulk Rashba effect to the existence of a three-dimensional topological insulator phase, with concomitant topological surface states even in the ultrathin film limit. Moreover, we predict that the topological transition, as induced by alloying, is followed by a Weyl semimetal phase of finite concentration extension, which is robust against disorder, putting forward hyperferroelectrics as promising candidates for spin-orbitronic applications.
Collapse
Affiliation(s)
- Domenico Di Sante
- Institut für Theoretische Physik und Astrophysik, Universität Würzburg, Am Hubland Campus Süd, Würzburg 97074, Germany
- Consiglio Nazionale delle Ricerche (CNR-SPIN), Via Vetoio, L'Aquila 67100, Italy
| | - Paolo Barone
- Consiglio Nazionale delle Ricerche (CNR-SPIN), Via Vetoio, L'Aquila 67100, Italy
- Graphene Labs, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova, Italy
| | - Alessandro Stroppa
- Consiglio Nazionale delle Ricerche (CNR-SPIN), Via Vetoio, L'Aquila 67100, Italy
| | - Kevin F Garrity
- Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg Maryland, 20899, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Silvia Picozzi
- Consiglio Nazionale delle Ricerche (CNR-SPIN), Via Vetoio, L'Aquila 67100, Italy
| |
Collapse
|
25
|
Lejaeghere K, Bihlmayer G, Björkman T, Blaha P, Blügel S, Blum V, Caliste D, Castelli IE, Clark SJ, Dal Corso A, de Gironcoli S, Deutsch T, Dewhurst JK, Di Marco I, Draxl C, Dułak M, Eriksson O, Flores-Livas JA, Garrity KF, Genovese L, Giannozzi P, Giantomassi M, Goedecker S, Gonze X, Grånäs O, Gross EKU, Gulans A, Gygi F, Hamann DR, Hasnip PJ, Holzwarth NAW, Iuşan D, Jochym DB, Jollet F, Jones D, Kresse G, Koepernik K, Küçükbenli E, Kvashnin YO, Locht ILM, Lubeck S, Marsman M, Marzari N, Nitzsche U, Nordström L, Ozaki T, Paulatto L, Pickard CJ, Poelmans W, Probert MIJ, Refson K, Richter M, Rignanese GM, Saha S, Scheffler M, Schlipf M, Schwarz K, Sharma S, Tavazza F, Thunström P, Tkatchenko A, Torrent M, Vanderbilt D, van Setten MJ, Van Speybroeck V, Wills JM, Yates JR, Zhang GX, Cottenier S. Reproducibility in density functional theory calculations of solids. Science 2016; 351:aad3000. [PMID: 27013736 DOI: 10.1126/science.aad3000] [Citation(s) in RCA: 414] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 02/19/2016] [Indexed: 11/02/2022]
Abstract
The widespread popularity of density functional theory has given rise to an extensive range of dedicated codes for predicting molecular and crystalline properties. However, each code implements the formalism in a different way, raising questions about the reproducibility of such predictions. We report the results of a community-wide effort that compared 15 solid-state codes, using 40 different potentials or basis set types, to assess the quality of the Perdew-Burke-Ernzerhof equations of state for 71 elemental crystals. We conclude that predictions from recent codes and pseudopotentials agree very well, with pairwise differences that are comparable to those between different high-precision experiments. Older methods, however, have less precise agreement. Our benchmark provides a framework for users and developers to document the precision of new applications and methodological improvements.
Collapse
Affiliation(s)
- Kurt Lejaeghere
- Center for Molecular Modeling, Ghent University, Technologiepark 903, BE-9052 Zwijnaarde, Belgium
| | - Gustav Bihlmayer
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA (Jülich Aachen Research Alliance), D-52425 Jülich, Germany
| | - Torbjörn Björkman
- Department of Physics, Åbo Akademi, FI-20500 Turku, Finland. Centre of Excellence in Computational Nanoscience (COMP) and Department of Applied Physics, Aalto University School of Science, Post Office Box 11100, FI-00076 Aalto, Finland
| | - Peter Blaha
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Stefan Blügel
- Peter Grünberg Institute and Institute for Advanced Simulation, Forschungszentrum Jülich and JARA (Jülich Aachen Research Alliance), D-52425 Jülich, Germany
| | - Volker Blum
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, NC 27708, USA
| | - Damien Caliste
- Université Grenoble Alpes, Institut Nanosciences et Cryogénie-Modeling and Material Exploration Department (INAC-MEM), Laboratoire de Simulation Atomistique (L_Sim), F-38042 Grenoble, France. Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), INAC-MEM, L_Sim, F-38054 Grenoble, France
| | - Ivano E Castelli
- Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Stewart J Clark
- Department of Physics, University of Durham, Durham DH1 3LE, UK
| | - Andrea Dal Corso
- International School for Advanced Studies (SISSA) and DEMOCRITOS, Consiglio Nazionale delle Ricerche-Istituto Officina dei Materiali (CNR-IOM), Via Bonomea 265, I-34136 Trieste, Italy
| | - Stefano de Gironcoli
- International School for Advanced Studies (SISSA) and DEMOCRITOS, Consiglio Nazionale delle Ricerche-Istituto Officina dei Materiali (CNR-IOM), Via Bonomea 265, I-34136 Trieste, Italy
| | - Thierry Deutsch
- Université Grenoble Alpes, Institut Nanosciences et Cryogénie-Modeling and Material Exploration Department (INAC-MEM), Laboratoire de Simulation Atomistique (L_Sim), F-38042 Grenoble, France. Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), INAC-MEM, L_Sim, F-38054 Grenoble, France
| | - John Kay Dewhurst
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Igor Di Marco
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden
| | - Claudia Draxl
- Institut für Physik and Integrative Research Institute for the Sciences (IRIS)-Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, D-12489 Berlin, Germany. Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Marcin Dułak
- Center for Atomic-Scale Materials Design, Department of Physics, Technical University of Denmark, DK-2800 Kongens Lyngby, Denmark
| | - Olle Eriksson
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden
| | - José A Flores-Livas
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Kevin F Garrity
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8553, Gaithersburg, MD 20899, USA
| | - Luigi Genovese
- Université Grenoble Alpes, Institut Nanosciences et Cryogénie-Modeling and Material Exploration Department (INAC-MEM), Laboratoire de Simulation Atomistique (L_Sim), F-38042 Grenoble, France. Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), INAC-MEM, L_Sim, F-38054 Grenoble, France
| | - Paolo Giannozzi
- Department of Mathematics, Computer Science, and Physics, University of Udine, Via delle Scienze 206, I-33100 Udine, Italy
| | - Matteo Giantomassi
- Institute of Condensed Matter and Nanosciences-Nanoscopic Physics (NAPS), Université Catholique de Louvain, Chemin des Étoiles 8, BE-1348 Louvain-la-Neuve, Belgium
| | - Stefan Goedecker
- Institut für Physik, Universität Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Xavier Gonze
- Institute of Condensed Matter and Nanosciences-Nanoscopic Physics (NAPS), Université Catholique de Louvain, Chemin des Étoiles 8, BE-1348 Louvain-la-Neuve, Belgium
| | - Oscar Grånäs
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden. School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA
| | - E K U Gross
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Andris Gulans
- Institut für Physik and Integrative Research Institute for the Sciences (IRIS)-Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, D-12489 Berlin, Germany. Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
| | - François Gygi
- Department of Computer Science, University of California-Davis, Davis, CA 95616, USA
| | - D R Hamann
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854-8019, USA. Mat-Sim Research, Post Office Box 742, Murray Hill, NJ 07974, USA
| | - Phil J Hasnip
- Department of Physics, University of York, Heslington, York YO10 5DD, UK
| | - N A W Holzwarth
- Department of Physics, Wake Forest University, Winston-Salem, NC 27109, USA
| | - Diana Iuşan
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden
| | - Dominik B Jochym
- Scientific Computing Department, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | | | - Daniel Jones
- Department of Materials, University of Oxford, 16 Parks Road, Oxford OX1 3PH, UK
| | - Georg Kresse
- Faculty of Physics and Center for Computational Materials Science, University of Vienna, Sensengasse 8/12, A-1090 Vienna, Austria
| | - Klaus Koepernik
- Leibniz‑Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, Post Office Box 270 116, D-01171 Dresden, Germany. Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, D-01069 Dresden, Germany
| | - Emine Küçükbenli
- Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland. International School for Advanced Studies (SISSA) and DEMOCRITOS, Consiglio Nazionale delle Ricerche-Istituto Officina dei Materiali (CNR-IOM), Via Bonomea 265, I-34136 Trieste, Italy
| | - Yaroslav O Kvashnin
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden
| | - Inka L M Locht
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden. Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands
| | - Sven Lubeck
- Institut für Physik and Integrative Research Institute for the Sciences (IRIS)-Adlershof, Humboldt-Universität zu Berlin, Zum Großen Windkanal 6, D-12489 Berlin, Germany
| | - Martijn Marsman
- Faculty of Physics and Center for Computational Materials Science, University of Vienna, Sensengasse 8/12, A-1090 Vienna, Austria
| | - Nicola Marzari
- Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Ulrike Nitzsche
- Leibniz‑Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, Post Office Box 270 116, D-01171 Dresden, Germany
| | - Lars Nordström
- Department of Physics and Astronomy, Division of Materials Theory, Uppsala University, Post Office Box 516, SE-75120 Uppsala, Sweden
| | - Taisuke Ozaki
- Institute for Solid State Physics, The University of Tokyo, Kashiwa 277-8581, Japan
| | - Lorenzo Paulatto
- Institut de Minéralogie, de Physique des Matériaux, et de Cosmochimie (IMPMC), Sorbonne Universités-Pierre and Marie Curie University Paris 06, Centre National de la Recherche Scientifique (CNRS) Unité Mixte de Recherche (UMR) 7590, Muséum National d'Histoire Naturelle, Institut de Recherche pour le Développement (IRD) Unité de Recherche 206, 4 Place Jussieu, F-75005 Paris, France
| | - Chris J Pickard
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, UK
| | - Ward Poelmans
- Center for Molecular Modeling, Ghent University, Technologiepark 903, BE-9052 Zwijnaarde, Belgium. High Performance Computing Unit, Ghent University, Krijgslaan 281 S9, BE-9000 Ghent, Belgium
| | - Matt I J Probert
- Department of Physics, University of York, Heslington, York YO10 5DD, UK
| | - Keith Refson
- Department of Physics, Royal Holloway, University of London, Egham TW20 0EX, UK. ISIS Facility, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Didcot OX11 0QX, UK
| | - Manuel Richter
- Leibniz‑Institut für Festkörper- und Werkstoffforschung (IFW) Dresden, Post Office Box 270 116, D-01171 Dresden, Germany. Dresden Center for Computational Materials Science (DCMS), Technische Universität Dresden, D-01069 Dresden, Germany
| | - Gian-Marco Rignanese
- Institute of Condensed Matter and Nanosciences-Nanoscopic Physics (NAPS), Université Catholique de Louvain, Chemin des Étoiles 8, BE-1348 Louvain-la-Neuve, Belgium
| | - Santanu Saha
- Institut für Physik, Universität Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Matthias Scheffler
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany. Department of Chemistry and Biochemistry and Materials Department, University of California-Santa Barbara, Santa Barbara, CA 93106-5050, USA
| | - Martin Schlipf
- Department of Computer Science, University of California-Davis, Davis, CA 95616, USA
| | - Karlheinz Schwarz
- Institute of Materials Chemistry, Vienna University of Technology, Getreidemarkt 9/165-TC, A-1060 Vienna, Austria
| | - Sangeeta Sharma
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Francesca Tavazza
- Material Measurement Laboratory, National Institute of Standards and Technology, 100 Bureau Drive, Stop 8553, Gaithersburg, MD 20899, USA
| | - Patrik Thunström
- Institute for Solid State Physics, Vienna University of Technology, A-1040 Vienna, Austria
| | - Alexandre Tkatchenko
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany. Physics and Materials Science Research Unit, University of Luxembourg, L-1511 Luxembourg
| | | | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, NJ 08854-8019, USA
| | - Michiel J van Setten
- Institute of Condensed Matter and Nanosciences-Nanoscopic Physics (NAPS), Université Catholique de Louvain, Chemin des Étoiles 8, BE-1348 Louvain-la-Neuve, Belgium
| | - Veronique Van Speybroeck
- Center for Molecular Modeling, Ghent University, Technologiepark 903, BE-9052 Zwijnaarde, Belgium
| | - John M Wills
- Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
| | - Jonathan R Yates
- Department of Materials, University of Oxford, 16 Parks Road, Oxford OX1 3PH, UK
| | - Guo-Xu Zhang
- Institute of Theoretical and Simulational Chemistry, School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, People's Republic of China
| | - Stefaan Cottenier
- Center for Molecular Modeling, Ghent University, Technologiepark 903, BE-9052 Zwijnaarde, Belgium. Department of Materials Science and Engineering, Ghent University, Technologiepark 903, BE-9052 Zwijnaarde, Belgium
| |
Collapse
|
26
|
Li MR, Croft M, Stephens PW, Ye M, Vanderbilt D, Retuerto M, Deng Z, Grams CP, Hemberger J, Hadermann J, Li WM, Jin CQ, Saouma FO, Jang JI, Akamatsu H, Gopalan V, Walker D, Greenblatt M. Mn2FeWO6: A New Ni3TeO6 -Type Polar and Magnetic Oxide. Adv Mater 2016; 28:2098. [PMID: 26970066 DOI: 10.1002/adma.201600479] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
|
27
|
Kim JW, Artyukhin S, Mun ED, Jaime M, Harrison N, Hansen A, Yang JJ, Oh YS, Vanderbilt D, Zapf VS, Cheong SW. Successive Magnetic-Field-Induced Transitions and Colossal Magnetoelectric Effect in Ni_{3}TeO_{6}. Phys Rev Lett 2015; 115:137201. [PMID: 26451580 DOI: 10.1103/physrevlett.115.137201] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Indexed: 06/05/2023]
Abstract
We report the discovery of a metamagnetic phase transition in a polar antiferromagnet Ni_{3}TeO_{6} that occurs at 52 T. The new phase transition accompanies a colossal magnetoelectric effect, with a magnetic-field-induced polarization change of 0.3 μC/cm^{2}, a value that is 4 times larger than for the spin-flop transition at 9 T in the same material, and also comparable to the largest magnetically induced polarization changes observed to date. Via density-functional calculations we construct a full microscopic model that describes the data. We model the spin structures in all fields and clarify the physics behind the 52 T transition. The high-field transition involves a competition between multiple different exchange interactions which drives the polarization change through the exchange-striction mechanism. The resultant spin structure is rather counterintuitive and complex, thus providing new insights on design principles for materials with strong magnetoelectric coupling.
Collapse
Affiliation(s)
- Jae Wook Kim
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - S Artyukhin
- IAMDN and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - E D Mun
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - M Jaime
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - N Harrison
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - A Hansen
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - J J Yang
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Y S Oh
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - D Vanderbilt
- IAMDN and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - V S Zapf
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S-W Cheong
- Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
28
|
Li MR, Croft M, Stephens PW, Ye M, Vanderbilt D, Retuerto M, Deng Z, Grams CP, Hemberger J, Hadermann J, Li WM, Jin CQ, Saouma FO, Jang JI, Akamatsu H, Gopalan V, Walker D, Greenblatt M. Mn2FeWO6 : A new Ni3TeO6-type polar and magnetic oxide. Adv Mater 2015; 27:2177-2181. [PMID: 25677612 DOI: 10.1002/adma.201405244] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2014] [Revised: 01/15/2015] [Indexed: 06/04/2023]
Abstract
Mn(2+)2 Fe(2+)W(6+)O6 , a new polar magnetic phase, adopts the corundum-derived Ni3TeO6 -type structure with large spontaneous polarization (PS) of 67.8 μC cm(-2), complex antiferromagnetic order below ≈75 K, and field-induced first-order transition to a ferrimagnetic phase below ≈30 K. First-principles calculations predict a ferrimagnetic (udu) ground state, optimal switching path along the c-axis, and transition to a lower energy udu-udd magnetic double cell.
Collapse
Affiliation(s)
- Man-Rong Li
- Department of Chemistry and Chemical Biology, Rutgers, the State University of New Jersey, 610 Taylor Road, Piscataway, NJ, 08854, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Abstract
We study the adiabatic pumping of the Chern-Simons axion (CSA) coupling along a parametric loop characterized by a nonzero second Chern number C^{(2)} from the viewpoint of the hybrid Wannier representation, in which the Wannier charge centers are visualized as sheets defined over a projected 2D Brillouin zone. We derive a new formula for the CSA coupling, expressing it as an integral involving Berry curvatures and potentials defined on the Wannier charge center sheets. We show that a loop characterized by a nonzero C^{(2)} requires a series of sheet-touching events at which 2π quanta of Berry curvature are passed from sheet to sheet, in such a way that e^{2}/h units of CSA coupling are pumped by a lattice vector by the end of the cycle. We illustrate these behaviors via explicit calculations on a model tight-binding Hamiltonian and discuss their implications.
Collapse
Affiliation(s)
- Maryam Taherinejad
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-0849, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-0849, USA
| |
Collapse
|
30
|
Garrity KF, Rabe KM, Vanderbilt D. Hyperferroelectrics: proper ferroelectrics with persistent polarization. Phys Rev Lett 2014; 112:127601. [PMID: 24724680 DOI: 10.1103/physrevlett.112.127601] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Indexed: 06/03/2023]
Abstract
All known proper ferroelectrics are unable to polarize normal to a surface or interface if the resulting depolarization field is unscreened, but there is no fundamental principle that enforces this behavior. In this work, we introduce hyperferroelectrics, a new class of proper ferroelectrics which polarize even when the depolarization field is unscreened, this condition being equivalent to instability of a longitudinal optic mode in addition to the transverse-optic-mode instability characteristic of proper ferroelectrics. We use first-principles calculations to show that several recently discovered hexagonal ferroelectric semiconductors have this property, and we examine its consequences both in the bulk and in a superlattice geometry.
Collapse
Affiliation(s)
- Kevin F Garrity
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Karin M Rabe
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
31
|
Oh YS, Artyukhin S, Yang JJ, Zapf V, Kim JW, Vanderbilt D, Cheong SW. Non-hysteretic colossal magnetoelectricity in a collinear antiferromagnet. Nat Commun 2014; 5:3201. [DOI: 10.1038/ncomms4201] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/06/2014] [Indexed: 11/09/2022] Open
|
32
|
Zhang H, Haule K, Vanderbilt D. Effective J=1/2 insulating state in Ruddlesden-Popper iridates: an LDA+DMFT study. Phys Rev Lett 2013; 111:246402. [PMID: 24483681 DOI: 10.1103/physrevlett.111.246402] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Indexed: 06/03/2023]
Abstract
Using ab initio methods for correlated electrons in solids, we investigate the metal-insulator transition across the Ruddlesden-Popper (RP) series of iridates and explore the robustness of the Jeff=1/2 state against band effects due to itineracy, tetragonal distortion, octahedral rotation, and Coulomb interaction. We predict the effects of epitaxial strain on the optical conductivity, magnetic moments, and Jeff=1/2 ground-state wave functions in the RP series. To describe the solution of the many-body problem in an intuitive picture, we introduce a concept of energy-dependent atomic states, which strongly resemble the atomic Jeff=1/2 states but with coefficients that are energy or time dependent. We demonstrate that the deviation from the ideal Jeff=1/2 state is negligible at short time scales for both single- and double-layer iridates, while it becomes quite significant for Sr3Ir2O7 at long times and low energy. Interestingly, Sr2IrO4 is positioned very close to the SU(2) limit, with only ∼3% deviation from the ideal Jeff=1/2 situation.
Collapse
Affiliation(s)
- Hongbin Zhang
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - Kristjan Haule
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
33
|
Abstract
We propose searching for Chern insulators by depositing atomic layers of elements with large spin-orbit coupling (e.g., Bi) on the surface of a magnetic insulator. We argue that such systems will typically have isolated surface bands with nonzero Chern numbers. If these overlap in energy, a metallic surface with large anomalous Hall conductivity will result; if not, a Chern-insulator state will typically occur. Thus, our search strategy reduces to looking for examples having the Fermi level in a global gap extending across the entire Brillouin zone. We verify this search strategy and identify several candidate systems by using first-principles calculations to compute the Chern number and anomalous Hall conductivity of a large number of such systems on MnTe, MnSe, and EuS surfaces. Our search reveals several promising Chern insulators with gaps of up to 140 meV.
Collapse
Affiliation(s)
- Kevin F Garrity
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | - David Vanderbilt
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| |
Collapse
|
34
|
Abstract
We use a first-principles rational-design approach to identify a previously unrecognized class of antiferroelectric materials in the Pnma MgSrSi structure type. The MgSrSi structure type can be described in terms of antipolar distortions of the nonpolar P6(3)/mmc ZrBeSi structure type, and we find many members of this structure type are close in energy to the related polar P6(3)mc LiGaGe structure type, which includes many members we predict to be ferroelectric. We highlight known ABC combinations in which this energy difference is comparable to the antiferroelectric-ferroelectric switching barrier of PbZrO(3). We calculate structural parameters and relative energies for all three structure types, both for reported and as-yet hypothetical representatives of this class. Our results provide guidance for the experimental realization and further investigation of high-performance materials suitable for practical applications.
Collapse
Affiliation(s)
- Joseph W Bennett
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | | | | | | |
Collapse
|
35
|
Abstract
We use a first-principles rational-design approach to identify a previously unrecognized class of ferroelectric materials in the P6(3)mc LiGaGe structure type. We calculate structural parameters, polarization, and ferroelectric well depths both for reported and as-yet hypothetical representatives of this class. Our results provide guidance for the experimental realization and further investigation of high-performance materials suitable for practical applications.
Collapse
Affiliation(s)
- Joseph W Bennett
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | | | | | | |
Collapse
|
36
|
Roy A, Bennett JW, Rabe KM, Vanderbilt D. Half-Heusler semiconductors as piezoelectrics. Phys Rev Lett 2012; 109:037602. [PMID: 22861897 DOI: 10.1103/physrevlett.109.037602] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 04/26/2012] [Indexed: 06/01/2023]
Abstract
We use a first-principles rational-design approach to demonstrate the potential of semiconducting half-Heusler compounds as a previously unrecognized class of piezoelectric materials. We perform a high-throughput scan of a large number of compounds, testing for insulating character and calculating structural, dielectric, and piezoelectric properties. Our results provide guidance for the experimental realization and characterization of high-performance materials in this class that may be suitable for practical applications.
Collapse
Affiliation(s)
- Anindya Roy
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854, USA
| | | | | | | |
Collapse
|
37
|
Abstract
AbstractOnly recently have there been fully quantum-mechanical calculations of two-dimensional surface stress tensors. We have calculated total energies and stresses of semiconductor surfaces within the Local Density Approximation, using norm-conserving pseudopotentials. In order to hasten convergence of the stress with respect to basis size, it is useful to remove a fictitious tensile stress. We have calculated surface stress for the relaxed Si (111) 1×1 and 2×2-adatom surfaces, as well as for the relaxed Ge (111) 1×1 and 2×2-adatom surfaces. We have also calculated the surface stress for several chemisorbed systems, including Ga, Ge and As chemisorbed onto Si. We find a dramatic correlation between the electronic structure and chemistry of the surface, and its elastic properties.
Collapse
|
38
|
Abstract
ABSTRACTMotivated by recent observations of coherent Ge island formation during growth of Ge on Si (100), we have carried out a theoretical study of the elastic energies associated with the evolution of a uniform strained overlayer as it segregates into coherent islands. In the context of a two-dimensional model, we have explored the conditions under which coherent islands may be energetically favored over both uniform epitaxial films and dislocated islands. We find that if the interface energy (for dislocated islands) is more than about 15% of the surface energy, then there is a range of island sizes for which the coherent island structure is preferred.
Collapse
|
39
|
Abstract
ABSTRACTWe present ab-initio calculations on energetics and geometries of atomic hydrogen, of several candidate acceptors, and of H-acceptor complexes in wurtzite GaN For the H-Mg complex in Mg-doped GaN, we calculate the vibrational frequencies of H. Hydrogen is found to be a negative-U center. H-acceptor complex formation is always exothermic. Substitutional Be has a low formation energy and a shallow impurity level, which makes it a good candidate for p-doping in MBE growth. CN appears not to be shallow. Atomic hydrogen incorporation in undoped GaN is disfavored in an H2 atmosphere; it becomes favorable in p and n-type conditions in atomic H environments.
Collapse
|
40
|
Satta A, Fiorentini V, Bosin A, Meloni F, Vanderbilt D. Structural and Electronic Properties of AlN, GaN And InN, and Band Offsets at AlN/GaN (1010) and (0001) Interfaces. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-395-515] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTAb initio local-density-functional calculations are presented for bulk A1N, GaN, and InN in the wurtzite, zincblende, and rocksalt structures. Structural transition pressures and deformation potentials of electronic gaps are investigated. In addition, we study the band offset at the polar (0001) and non-polar (1010) AIN/GaN interfaces. Within AIN-on-GaN epitaxial conditions, we obtain valence-band offset values close to 0.7 eV for both interfaces. From the macroscopic field appearing along the growth direction of the polar interface (tentatively attributed to AIN macroscopic polarization), an estimate of the macroscopic dielectric constant of GaN is extracted. All calculations employed conjugate-gradient total-energy minimizations, ultrasoft pseudopotentials, and plane waves at 25 Ryd cutoff.
Collapse
|
41
|
Abstract
ABSTRACTThe strain induced by lattice mismatch at the interface is responsible for the different value of the band discontinuities observed recently for the AlN/GaN (AlN on GaN) and the GaN/AlN (GaN on AlN) polar (0001) interface. We present a first-principles calculation of valence band offsets, interface dipoles, strain-induced piezoelectric fields, relaxed geometric structure, and formation energies. Our results confirm the existence of a large forward-backward asymmetry for this interface.
Collapse
|
42
|
Abstract
We investigate the phase diagrams of RMn(2)O(5) via a first-principles effective-Hamiltonian method. We are able to reproduce the most important features of the complicated magnetic and ferroelectric phase transitions. The calculated polarization as a function of temperature agrees very well with experiments. The dielectric-constant step at the commensurate-to-incommensurate magnetic phase transition is well reproduced. The microscopic mechanisms for the phase transitions are discussed.
Collapse
Affiliation(s)
- Kun Cao
- Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, 230026, People's Republic of China
| | | | | | | |
Collapse
|
43
|
Stengel M, Vanderbilt D, Spaldin NA. Enhancement of ferroelectricity at metal-oxide interfaces. Nat Mater 2009; 8:392-7. [PMID: 19377465 DOI: 10.1038/nmat2429] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2008] [Accepted: 03/18/2009] [Indexed: 05/10/2023]
Abstract
The development of ultrathin ferroelectric capacitors for use in memory applications has been hampered by depolarization effects arising from the electrode-film interfaces. These can be characterized in terms of a reduced interface capacitance, or equivalently an 'effective dead layer' in contact with the electrode. Here, by performing first-principles calculations on four capacitor structures based on BaTiO(3) and PbTiO(3), we determine the intrinsic interfacial effects responsible for destabilizing the ferroelectric state in ultrathin-film devices. Although it has been widely believed that these are governed by the electronic screening properties at the interface, we show that they also depend crucially on the local chemical environment through the force constants of the metal oxide bonds. In particular, in the case of interfaces formed between AO-terminated perovskites and simple metals, we demonstrate a novel mechanism of interfacial ferroelectricity that produces an overall enhancement of the ferroelectric instability of the film, rather than its suppression as is usually assumed. The resulting 'negative dead layer' suggests a route to thin-film ferroelectric devices that are free of deleterious size effects.
Collapse
Affiliation(s)
- Massimiliano Stengel
- Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | | | | |
Collapse
|
44
|
Essin AM, Moore JE, Vanderbilt D. Magnetoelectric polarizability and axion electrodynamics in crystalline insulators. Phys Rev Lett 2009; 102:146805. [PMID: 19392469 DOI: 10.1103/physrevlett.102.146805] [Citation(s) in RCA: 181] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2008] [Indexed: 05/22/2023]
Abstract
The orbital motion of electrons in a three-dimensional solid can generate a pseudoscalar magnetoelectric coupling theta, a fact we derive for the single-particle case using a recent theory of polarization in weakly inhomogeneous materials. This polarizability theta is the same parameter that appears in the "axion electrodynamics" Lagrangian DeltaL_{EM}=(thetae;{2}/2pih)E.B, which is known to describe the unusual magnetoelectric properties of the three-dimensional topological insulator (theta=pi). We compute theta for a simple model that accesses the topological insulator and discuss its connection to the surface Hall conductivity. The orbital magnetoelectric polarizability can be generalized to the many-particle wave function and defines the 3D topological insulator, like the integer quantum Hall effect, in terms of a topological ground-state response function.
Collapse
Affiliation(s)
- Andrew M Essin
- Department of Physics, University of California, Berkeley, California 94720, USA
| | | | | |
Collapse
|
45
|
Abstract
We extend the Berry-phase concept of polarization to insulators having a nonzero value of the Chern invariant. The generalization to such Chern insulators requires special care because of the partial occupation of chiral edge states. We show how the integrated bulk current arising from an adiabatic evolution can be related to a difference of bulk polarizations. We also show how the surface charge can be related to the bulk polarization, but only with a knowledge of the wave vector at which the occupancy of the edge state is discontinuous. Furthermore, we present numerical calculations on a model Hamiltonian to provide additional support for our analytic arguments.
Collapse
Affiliation(s)
- Sinisa Coh
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
| | | |
Collapse
|
46
|
Thonhauser T, Ceresoli D, Mostofi AA, Marzari N, Resta R, Vanderbilt D. A converse approach to the calculation of NMR shielding tensors. J Chem Phys 2009. [DOI: 10.1063/1.3216028] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
47
|
Wu X, Stengel M, Rabe KM, Vanderbilt D. Predicting polarization and nonlinear dielectric response of arbitrary perovskite superlattice sequences. Phys Rev Lett 2008; 101:087601. [PMID: 18764661 DOI: 10.1103/physrevlett.101.087601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Indexed: 05/26/2023]
Abstract
We carry out first-principles calculations of the nonlinear dielectric response of short-period ferroelectric superlattices. We compute and store not only the total polarization, but also the Wannier-based polarizations of individual atomic layers, as a function of the electric displacement field, and use this information to construct a model capable of predicting the nonlinear dielectric response of an arbitrary superlattice sequence. We demonstrate the successful application of our approach to superlattices composed of SrTiO3, CaTiO3, and BaTiO3 layers.
Collapse
Affiliation(s)
- Xifan Wu
- Chemistry Department, Princeton University, Princeton, New Jersey 08544-0001, USA
| | | | | | | |
Collapse
|
48
|
Abstract
We carry out a first-principles theoretical study of the magnetically induced polarization in orthorhombic TbMnO3, a prototypical material in which a cycloidal-spin structure generates an electric polarization via the spin-orbit interaction. We compute both the electronic and the lattice-mediated contributions to the polarization and find that the latter is strongly dominant. We analyze the spin-orbit induced forces and lattice displacements from both atomic and mode-decomposition viewpoints, and show that a simple model based on nearest Mn-Mn neighbor Dzyaloshinskii-Moriya interactions is not able to account fully for the results. The direction and magnitude of our computed polarization are in good agreement with experiment.
Collapse
Affiliation(s)
- Andrei Malashevich
- Department of Physics & Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
| | | |
Collapse
|
49
|
Lee HN, Nakhmanson SM, Chisholm MF, Christen HM, Rabe KM, Vanderbilt D. Suppressed dependence of polarization on epitaxial strain in highly polar ferroelectrics. Phys Rev Lett 2007; 98:217602. [PMID: 17677807 DOI: 10.1103/physrevlett.98.217602] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2006] [Indexed: 05/16/2023]
Abstract
A combined experimental and computational investigation of coupling between polarization and epitaxial strain in highly polar ferroelectric PbZr(0.2)Ti(0.8)O3 (PZT) thin films is reported. A comparison of the properties of relaxed (tetragonality c/a approximately 1.05) and highly strained (c/a approximately 1.09) epitaxial films shows that polarization, while being amongst the highest reported for PZT or PbTiO3 in either film or bulk forms P(r) approximately 82 microC/cm(2)), is almost independent of the epitaxial strain. We attribute this behavior to a suppressed sensitivity of the A-site cations to epitaxial strain in these Pb-based perovskites, where the ferroelectric displacements are already large, contrary to the case of less polar perovskites, such as BaTiO3. In the latter case, the A-site cation (Ba) and equatorial oxygen displacements can lead to substantial polarization increases.
Collapse
Affiliation(s)
- Ho Nyung Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
| | | | | | | | | | | |
Collapse
|
50
|
Wu X, Diéguez O, Rabe KM, Vanderbilt D. Wannier-based definition of layer polarizations in perovskite superlattices. Phys Rev Lett 2006; 97:107602. [PMID: 17025854 DOI: 10.1103/physrevlett.97.107602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Indexed: 05/12/2023]
Abstract
In insulators, the method of Marzari and Vanderbilt [Phys. Rev. B 56, 12 847 (1997)] can be used to generate maximally localized Wannier functions whose centers are related to the electronic polarization. In the case of layered insulators, this approach can be adapted to provide a natural definition of the local polarization associated with each layer, based on the locations of the nuclear charges and one-dimensional Wannier centers comprising each layer. Here, we use this approach to compute and analyze layer polarizations of ferroelectric perovskite superlattices, including changes in layer polarizations induced by sublattice displacements (i.e., layer-decomposed Born effective charges) and local symmetry breaking at the interfaces. The method provides a powerful tool for analyzing the polarization-related properties of complex layered oxide systems.
Collapse
Affiliation(s)
- Xifan Wu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA
| | | | | | | |
Collapse
|