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Liu WC, Chiu YH, Kung YY, Liao PY, Cheng CH, Chih YC, Tsai YW, Chu CH, Lai CH, Huang DJ, Soo YL, Chang SL. Revisiting La 0.5Sr 1.5MnO 4 lattice distortion and charge ordering with multi-beam resonant diffraction. ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2017; 73:46-53. [PMID: 28042803 DOI: 10.1107/s2053273316013759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 08/27/2016] [Indexed: 11/11/2022]
Abstract
Sinusoidal wave type distortions of La0.5Sr1.5MnO4 in the low-temperature orthorhombic phase were observed using multi-beam resonant X-ray diffraction (MRXD) with (7/4 7/4 0) fractional primary diffraction. Two four-beam diffractions with opposite asymmetry were measured at 6.5545 keV and compared with the curves simulated by the dynamical X-ray diffraction theory. This approach provides the possibility of resolving the distortion modes which are perpendicular to the momentum transfer by a single azimuthal scan. The paper also demonstrates the sensitivity of MRXD profiles versus incident X-ray energy in the vicinity of the Mn K edge to the charge disproportion between the two manganese sites, reconfirming the small charge disproportion feature.
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Affiliation(s)
- Wen Chung Liu
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Yi Hua Chiu
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Ying Yu Kung
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Po Yu Liao
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Chih Hao Cheng
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Yu Chieh Chih
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Yi Wei Tsai
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Chia Hung Chu
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Chia Hung Lai
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Di Jing Huang
- National Synchrotron Radiation Research Center, Hsinchu, 30076, Taiwan
| | - Yun Liang Soo
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Shih Lin Chang
- Department of Physics, Tsing Hua University, Hsinchu, 30013, Taiwan
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Wall S, Trigo M. Recent Developments in Ultrafast X-ray Techniques for Materials Science Applications. ACTA ACUST UNITED AC 2016. [DOI: 10.1080/08940886.2016.1220273] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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3
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Mankowsky R, Först M, Cavalleri A. Non-equilibrium control of complex solids by nonlinear phononics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:064503. [PMID: 27223639 DOI: 10.1088/0034-4885/79/6/064503] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We review some recent advances in the use of optical fields at terahertz frequencies to drive the lattice of complex materials. We will focus on the control of low energy collective properties of solids, which emerge on average when a high frequency vibration is driven and a new crystal structure induced. We first discuss the fundamentals of these lattice rearrangements, based on how anharmonic mode coupling transforms an oscillatory motion into a quasi-static deformation of the crystal structure. We then discuss experiments, in which selectively changing a bond angle turns an insulator into a metal, accompanied by changes in charge, orbital and magnetic order. We then address the case of light induced non-equilibrium superconductivity, a mysterious phenomenon observed in some cuprates and molecular materials when certain lattice vibrations are driven. Finally, we show that the dynamics of electronic and magnetic phase transitions in complex-oxide heterostructures follow distinctly new physical pathways in case of the resonant excitation of a substrate vibrational mode.
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Affiliation(s)
- Roman Mankowsky
- Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany
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4
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Radaelli PG, Dhesi SS. The contribution of Diamond Light Source to the study of strongly correlated electron systems and complex magnetic structures. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015; 373:rsta.2013.0148. [PMID: 25624510 DOI: 10.1098/rsta.2013.0148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We review some of the significant contributions to the field of strongly correlated materials and complex magnets, arising from experiments performed at the Diamond Light Source (Harwell Science and Innovation Campus, Didcot, UK) during the first few years of operation (2007-2014). We provide a comprehensive overview of Diamond research on topological insulators, multiferroics, complex oxides and magnetic nanostructures. Several experiments on ultrafast dynamics, magnetic imaging, photoemission electron microscopy, soft X-ray holography and resonant magnetic hard and soft X-ray scattering are described.
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Affiliation(s)
- P G Radaelli
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK
| | - S S Dhesi
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
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Fink J, Schierle E, Weschke E, Geck J. Resonant elastic soft x-ray scattering. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2013; 76:056502. [PMID: 23563216 DOI: 10.1088/0034-4885/76/5/056502] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Resonant (elastic) soft x-ray scattering (RSXS) offers a unique element, site and valence specific probe to study spatial modulations of charge, spin and orbital degrees of freedom in solids on the nanoscopic length scale. It is not only used to investigate single-crystalline materials. This method also enables one to examine electronic ordering phenomena in thin films and to zoom into electronic properties emerging at buried interfaces in artificial heterostructures. During the last 20 years, this technique, which combines x-ray scattering with x-ray absorption spectroscopy, has developed into a powerful probe to study electronic ordering phenomena in complex materials and furthermore delivers important information on the electronic structure of condensed matter. This review provides an introduction to the technique, covers the progress in experimental equipment, and gives a survey on recent RSXS studies of ordering in correlated electron systems and at interfaces.
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Affiliation(s)
- J Fink
- Leibniz-Institute for Solid State and Materials Research Dresden, PO Box 270116, D-01171 Dresden, Germany.
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6
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Benjamin D, Abanin D, Abbamonte P, Demler E. Microscopic theory of resonant soft-x-ray scattering in materials with charge order: the example of charge stripes in high-temperature cuprate superconductors. PHYSICAL REVIEW LETTERS 2013; 110:137002. [PMID: 23581360 DOI: 10.1103/physrevlett.110.137002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2012] [Indexed: 06/02/2023]
Abstract
We present a microscopic theory of resonant soft-x-ray scattering that accounts for the delocalized character of valence electrons. Unlike past approaches based on local form factors, our functional determinant method treats realistic band structures. This method builds upon earlier theoretical work in mesoscopic physics and accounts for excitonic effects as well as the orthogonality catastrophe arising from interaction between the core hole and the valence band electrons. We show that the two-peak structure observed near the O K edge of stripe-ordered La1.875Ba0.125CuO4 is due to dynamical nesting within the canonical cuprate band structure. Our results provide evidence for reasonably well-defined, high-energy quasiparticles in cuprates and establish resonant soft-x-ray scattering as a bulk-sensitive probe of the electron quasiparticles.
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Affiliation(s)
- David Benjamin
- Physics Department, Harvard University, Cambridge, Massachusetts 02138, USA
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7
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Tanaka A, Chang CF, Buchholz M, Trabant C, Schierle E, Schlappa J, Schmitz D, Ott H, Metcalf P, Tjeng LH, Schüßler-Langeheine C. Symmetry of orbital order in Fe3O4 studied by Fe L(2,3) resonant x-ray diffraction. PHYSICAL REVIEW LETTERS 2012; 108:227203. [PMID: 23003646 DOI: 10.1103/physrevlett.108.227203] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Indexed: 06/01/2023]
Abstract
We studied the symmetry of the Fe 3d wave function in magnetite below the Verwey temperature T(V) with resonant soft-x-ray diffraction. Although the lattice structure of the low-temperature phase of Fe(3)O(4) is well described by the pseudo-orthorhombic Pmca with a slight monoclinic P2/c distortion, we find that the 3d wave function does not reflect the Pmca symmetry, and its distortion toward monoclinic symmetry is by far larger than that of the lattice. The result supports a scenario in which the Verwey transition involves the ordering of t(2g) orbitals with complex-number coefficients.
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Affiliation(s)
- A Tanaka
- Department of Quantum Matters, ADSM, Hiroshima University, Higashi-Hiroshima 739-8530, Japan
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8
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Schlappa J, Chang CF, Hu Z, Schierle E, Ott H, Weschke E, Kaindl G, Huijben M, Rijnders G, Blank DHA, Tjeng LH, Schüssler-Langeheine C. Resonant soft x-ray scattering from stepped surfaces of SrTiO3. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:035501. [PMID: 22179392 DOI: 10.1088/0953-8984/24/3/035501] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We studied the resonant diffraction signal from stepped surfaces of SrTiO(3) at the Ti 2p → 3d (L(2,3)) resonance in comparison with x-ray absorption (XAS) and specular reflectivity data. The steps on the surface form an artificial superstructure suitable as a model system for resonant soft x-ray diffraction. A small step density on the surface is sufficient to produce a well defined diffraction peak. We determined the optical parameters of the sample across the resonance and found that the differences between the energy dependence of the x-ray absorption signal, the specular reflectivity and the step-related peak reflect the different quantities probed in these signals. When recorded at low incidence or detection angles, XAS and specular reflectivity spectra are strongly distorted by the changes of the angle of total reflection with energy. The resonant diffraction spectrum is less affected and can be used as a spectroscopic probe even in less favorable geometries.
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Affiliation(s)
- J Schlappa
- II. Physikalisches Institut, Universität zu Köln, Köln, Germany.
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9
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Doering D, Chuang YD, Andresen N, Chow K, Contarato D, Cummings C, Domning E, Joseph J, Pepper JS, Smith B, Zizka G, Ford C, Lee WS, Weaver M, Patthey L, Weizeorick J, Hussain Z, Denes P. Development of a compact fast CCD camera and resonant soft x-ray scattering endstation for time-resolved pump-probe experiments. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:073303. [PMID: 21806178 DOI: 10.1063/1.3609862] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The designs of a compact, fast CCD (cFCCD) camera, together with a resonant soft x-ray scattering endstation, are presented. The cFCCD camera consists of a highly parallel, custom, thick, high-resistivity CCD, readout by a custom 16-channel application specific integrated circuit to reach the maximum readout rate of 200 frames per second. The camera is mounted on a virtual-axis flip stage inside the RSXS chamber. When this flip stage is coupled to a differentially pumped rotary seal, the detector assembly can rotate about 100°/360° in the vertical/horizontal scattering planes. With a six-degrees-of-freedom cryogenic sample goniometer, this endstation has the capability to detect the superlattice reflections from the electronic orderings showing up in the lower hemisphere. The complete system has been tested at the Advanced Light Source, Lawrence Berkeley National Laboratory, and has been used in multiple experiments at the Linac Coherent Light Source, SLAC National Accelerator Laboratory.
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Affiliation(s)
- D Doering
- Engineering Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, California 94720, USA.
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10
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Ehrke H, Tobey RI, Wall S, Cavill SA, Först M, Khanna V, Garl T, Stojanovic N, Prabhakaran D, Boothroyd AT, Gensch M, Mirone A, Reutler P, Revcolevschi A, Dhesi SS, Cavalleri A. Photoinduced melting of antiferromagnetic order in La(0.5)Sr(1.5)MnO4 measured using ultrafast resonant soft x-ray diffraction. PHYSICAL REVIEW LETTERS 2011; 106:217401. [PMID: 21699341 DOI: 10.1103/physrevlett.106.217401] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Indexed: 05/15/2023]
Abstract
We used ultrafast resonant soft x-ray diffraction to probe the picosecond dynamics of spin and orbital order in La(0.5)Sr(1.5)MnO(4) after photoexcitation with a femtosecond pulse of 1.5 eV radiation. Complete melting of antiferromagnetic spin order is evidenced by the disappearance of a (1/4,1/4,1/2) diffraction peak. On the other hand, the (1/4,1/4,0) diffraction peak, reflecting orbital order, is only partially reduced. We interpret the results as evidence of destabilization in the short-range exchange pattern with no significant relaxation of the long-range Jahn-Teller distortions. Cluster calculations are used to analyze different possible magnetically ordered states in the long-lived metastable phase. Nonthermal coupling between light and magnetism emerges as a primary aspect of photoinduced phase transitions in manganites.
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Affiliation(s)
- H Ehrke
- Department of Physics, Clarendon Laboratory, University of Oxford, Oxford, United Kingdom
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11
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Zhou SY, Zhu Y, Langner MC, Chuang YD, Yu P, Yang WL, Cruz Gonzalez AG, Tahir N, Rini M, Chu YH, Ramesh R, Lee DH, Tomioka Y, Tokura Y, Hussain Z, Schoenlein RW. Ferromagnetic enhancement of CE-type spin ordering in (Pr,Ca)MnO3. PHYSICAL REVIEW LETTERS 2011; 106:186404. [PMID: 21635110 DOI: 10.1103/physrevlett.106.186404] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Indexed: 05/30/2023]
Abstract
We present resonant soft x-ray scattering results from small bandwidth manganites (Pr,Ca)MnO(3), which show that the CE-type spin ordering (SO) at the phase boundary is stabilized only below the canted antiferromagnetic transition temperature and enhanced by ferromagnetism in the macroscopically insulating state (FM-I). Our results reveal the fragility of the CE-type ordering that underpins the colossal magnetoresistance effect in this system, as well as an unexpected cooperative interplay between FM-I and CE-type SO which is in contrast to the competitive interplay between the ferromagnetic metallic state and CE-type ordering.
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Affiliation(s)
- S Y Zhou
- Advanced Light Source, Lawrence Berkeley National Laboratory, California 94720, USA.
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12
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Beale TAW, Hase TPA, Iida T, Endo K, Steadman P, Marshall AR, Dhesi SS, van der Laan G, Hatton PD. RASOR: an advanced instrument for soft x-ray reflectivity and diffraction. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:073904. [PMID: 20687739 DOI: 10.1063/1.3458004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We report the design and construction of a novel soft x-ray diffractometer installed at Diamond Light Source. The beamline endstation RASOR is constructed for general users and designed primarily for the study of single crystal diffraction and thin film reflectivity. The instrument is comprised of a limited three circle (theta, 2theta, and chi) diffractometer with an additional removable rotation (phi) stage. It is equipped with a liquid helium cryostat, and post-scatter polarization analysis. Motorized motions are provided for the precise positioning of the sample onto the diffractometer center of rotation, and for positioning the center of rotation onto the x-ray beam. The functions of the instrument have been tested at Diamond Light Source, and initial test measurements are provided, demonstrating the potential of the instrument.
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Affiliation(s)
- T A W Beale
- Department of Physics, Durham University, South Road, Durham DH1 3LE, United Kingdom
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13
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Wilkins SB, Forrest TR, Beale TAW, Bland SR, Walker HC, Mannix D, Yakhou F, Prabhakaran D, Boothroyd AT, Hill JP, Hatton PD, McMorrow DF. Nature of the magnetic order and origin of induced ferroelectricity in TbMnO3. PHYSICAL REVIEW LETTERS 2009; 103:207602. [PMID: 20366013 DOI: 10.1103/physrevlett.103.207602] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Indexed: 05/29/2023]
Abstract
The magnetic structures which endow TbMnO(3) with its multiferroic properties have been reassessed on the basis of a comprehensive soft x-ray resonant scattering (XRS) study. The selectivity of XRS facilitated separation of the various contributions (Mn L(2) edge, Mn 3d moments; Tb M(4) edge, Tb 4f moments), while its variation with azimuth provided information on the moment direction of distinct Fourier components. When the data are combined with a detailed group theory analysis, a new picture emerges of the ferroelectric transition at 28 K. Instead of being driven by the transition from a collinear to a noncollinear magnetic structure, as has previously been supposed, it is shown to occur between two noncollinear structures.
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Affiliation(s)
- S B Wilkins
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Lab, Upton, New York 11973-5000, USA
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14
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Takeuchi T, Chainani A, Takata Y, Tanaka Y, Oura M, Tsubota M, Senba Y, Ohashi H, Mochiku T, Hirata K, Shin S. An ultrahigh-vacuum apparatus for resonant diffraction experiments using soft x rays (hnu=300-2000 eV). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2009; 80:023905. [PMID: 19256660 DOI: 10.1063/1.3078269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have developed an ultrahigh-vacuum instrument for resonant diffraction experiments using polarized soft x rays in the energy range of hnu=300-2000 eV at beamline BL17SU of SPring-8. The diffractometer consists of modified differentially pumped rotary feedthroughs for theta-2theta stages, a sample manipulator with motor-controlled x-y-z-, tilt (chi)-, and azimuth (phi)-axes, and a liquid helium flow-type cryostat for temperature dependent measurements between 30 and 300 K. Test results indicate that the diffractometer exhibits high reproducibility (better than 0.001 degrees ) for a Bragg reflection of alpha-quartz 100 at a photon energy of hnu=1950 eV. Typical off- and on-resonance Bragg reflections in the energy range of 530-1950 eV could be measured using the apparatus. The results show that x-ray diffraction experiments with energy-, azimuth-, and incident photon polarization-dependence can be reliably measured using soft x rays in the energy range of approximately 300-2000 eV. The facility can be used for resonant diffraction experiments across the L-edge of transition metals, M-edge of lanthanides, and up to the Si K-edge of materials.
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Affiliation(s)
- T Takeuchi
- RIKEN SPring-8 Center, 1-1-1 Kouto Sayo-cho Sayo-gun, Hyogo 679-5148, Japan
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15
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Wakabayashi Y, Upton MH, Grenier S, Hill JP, Nelson CS, Kim JW, Ryan PJ, Goldman AI, Zheng H, Mitchell JF. Surface effects on the orbital order in the single-layered manganite La0.5Sr1.5MnO4. NATURE MATERIALS 2007; 6:972-976. [PMID: 18026106 DOI: 10.1038/nmat2061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Accepted: 10/15/2007] [Indexed: 05/25/2023]
Abstract
The question of how bulk electronic order is terminated at a surface is an intriguing one, and one with possible practical implications--for example in nanoscaled systems that may be characterized by their surface behaviour. One example of such order is orbital order, and in principle it should be possible to probe the termination of this order with surface X-ray scattering. Here, we report the first observation of the scattering arising from the termination of bulk orbital order at the surface of a crystal--so-called 'orbital truncation rods'. The measurements, carried out on a cleaved perovskite, La(0.5)Sr(1.5)MnO(4), reveal that whereas the crystallographic surface is atomically smooth, the orbital 'surface', which is observed through the atomic displacements caused by the orbital order, is much rougher, with a typical scale of the surface roughness of approximately 7 degrees A. Interestingly, the temperature dependence of this scattering shows evidence of a surface-induced second-order transition.
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Affiliation(s)
- Y Wakabayashi
- Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba 305-0801, Japan.
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16
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Smadici S, Abbamonte P, Bhattacharya A, Zhai X, Jiang B, Rusydi A, Eckstein JN, Bader SD, Zuo JM. Electronic reconstruction at SrMnO3-LaMnO3 superlattice interfaces. PHYSICAL REVIEW LETTERS 2007; 99:196404. [PMID: 18233095 DOI: 10.1103/physrevlett.99.196404] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Indexed: 05/25/2023]
Abstract
We use resonant soft-x-ray scattering (RSXS) to study the electronic reconstruction at the interface between the Mott insulator LaMnO3 and the band insulator SrMnO3. Superlattices of these two insulators were shown previously to have both ferromagnetism and metallic tendencies [Koida, Phys. Rev. B 66, 144418 (2002)10.1103/PhysRevB.66.144418]. By studying a judiciously chosen superlattice reflection, we show that the interface density of states exhibits a pronounced peak at the Fermi level, similar to that predicted in related titanate superlattices by Okamoto et al. [Phys. Rev. B 70, 241104(R) (2004)10.1103/PhysRevB.70.241104]. The intensity of this peak correlates with the conductivity and magnetization, suggesting it is the driver of metallic behavior. Our study demonstrates a general strategy for using RSXS to probe the electronic properties of heterostructure interfaces.
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Affiliation(s)
- Serban Smadici
- Frederick Seitz Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA
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17
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Chi S, Ye F, Dai P, Fernandez-Baca JA, Huang Q, Lynn JW, Plummer EW, Mathieu R, Kaneko Y, Tokura Y. Effect of antiferromagnetic spin correlations on lattice distortion and charge ordering in Pr0.5Ca1.5MnO4. Proc Natl Acad Sci U S A 2007; 104:10796-801. [PMID: 17578911 PMCID: PMC1894565 DOI: 10.1073/pnas.0704303104] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2007] [Indexed: 11/18/2022] Open
Abstract
We use neutron scattering to study the lattice and magnetic structure of the layered half-doped manganite Pr(0.5)Ca(1.5)MnO(4). On cooling from high temperature, the system first becomes charge-and orbital-ordered (CO/OO) near T(CO) = 300 K and then develops checkerboard-like antiferromagnetic (AF) order below T(N) = 130 K. At temperatures above T(N) but below T(CO) (T(N)
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Affiliation(s)
- Songxue Chi
- *Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200
| | - F. Ye
- Oak Ridge National Laboratory, Oak Ridge, TN 37831-6393
| | - Pengcheng Dai
- *Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200
- Oak Ridge National Laboratory, Oak Ridge, TN 37831-6393
| | - J. A. Fernandez-Baca
- *Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200
- Oak Ridge National Laboratory, Oak Ridge, TN 37831-6393
| | - Q. Huang
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899-6102
| | - J. W. Lynn
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD 20899-6102
| | - E. W. Plummer
- *Department of Physics and Astronomy, University of Tennessee, Knoxville, TN 37996-1200
- Oak Ridge National Laboratory, Oak Ridge, TN 37831-6393
| | - R. Mathieu
- Spin Structure Project (ERATO), Japan Science and Technology Corporation, Advanced Industrial Science and Technology Central 4, Tsukuba 305-8562, Japan; and
| | - Y. Kaneko
- Spin Structure Project (ERATO), Japan Science and Technology Corporation, Advanced Industrial Science and Technology Central 4, Tsukuba 305-8562, Japan; and
| | - Y. Tokura
- Spin Structure Project (ERATO), Japan Science and Technology Corporation, Advanced Industrial Science and Technology Central 4, Tsukuba 305-8562, Japan; and
- Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan
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18
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Rusydi A, Abbamonte P, Eisaki H, Fujimaki Y, Blumberg G, Uchida S, Sawatzky GA. Quantum melting of the hole crystal in the spin ladder of Sr(14-x)CaxCu24O41. PHYSICAL REVIEW LETTERS 2006; 97:016403. [PMID: 16907390 DOI: 10.1103/physrevlett.97.016403] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Indexed: 05/11/2023]
Abstract
We have used resonant soft x-ray scattering to study the effects of discommensuration on the hole Wigner crystal (HC) in the spin ladder Sr(14-x)CaxCu24O41 (SCCO). As the hole density is varied the HC forms only with the commensurate wave vectors L(L) = 1/5 and L(L) = 1/3; for incommensurate values it "melts." A simple scaling between L(L) and temperature is observed, tau1/3/tau1/5 = 5/3, indicating an inverse relationship between the interaction strength and wavelength. Our results suggest that SCCO contains hole pairs that are crystallized through an interplay between lattice commensuration and Coulomb repulsion, reminiscent of the "pair density wave" scenario.
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Affiliation(s)
- A Rusydi
- National Synchrotron Light Source, Brookhaven National Laboratory, Upton, New York, 11973-5000, USA
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Senff D, Krüger F, Scheidl S, Benomar M, Sidis Y, Demmel F, Braden M. Spin-wave dispersion in orbitally ordered La1/2Sr3/2MnO4. PHYSICAL REVIEW LETTERS 2006; 96:257201. [PMID: 16907336 DOI: 10.1103/physrevlett.96.257201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Indexed: 05/11/2023]
Abstract
The magnon dispersion in the charge, orbital, and spin ordered phase in La1/2Sr3/2MnO4 has been studied by means of inelastic neutron scattering. We find excellent agreement with a magnetic interaction model based on the CE-type superstructure. The magnetic excitations are dominated by ferromagnetic exchange parameters revealing a nearly one-dimensional character at high energies. The strong ferromagnetic interaction in the charge or orbital ordered phase appears to be essential for the capability of manganites to switch between metallic and insulating phases.
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Affiliation(s)
- D Senff
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
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Schüssler-Langeheine C, Schlappa J, Tanaka A, Hu Z, Chang CF, Schierle E, Benomar M, Ott H, Weschke E, Kaindl G, Friedt O, Sawatzky GA, Lin HJ, Chen CT, Braden M, Tjeng LH. Spectroscopy of stripe order in La1.8Sr0.2NiO4 using resonant soft x-ray diffraction. PHYSICAL REVIEW LETTERS 2005; 95:156402. [PMID: 16241744 DOI: 10.1103/physrevlett.95.156402] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Indexed: 05/05/2023]
Abstract
Strong resonant enhancements of the charge-order and spin-order superstructure-diffraction intensities in La1.8Sr0.2NiO4 are observed when x-ray energies in the vicinity of the Ni L2,3 absorption edges are used. The pronounced photon-energy and polarization dependences of these diffraction intensities allow for a critical determination of the local symmetry of the ordered spin and charge carriers. We found that not only the antiferromagnetic order but also the charge-order superstructure resides within the NiO2 layers; the holes are mainly located on in-plane oxygens surrounding a Ni2+ site with the spins coupled antiparallel in close analogy to Zhang-Rice singlets in the cuprates.
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Affiliation(s)
- C Schüssler-Langeheine
- II. Physikalisches Institut, Universität zu Köln, Zülpicher Strasse 77, D-50937 Köln, Germany
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Zegkinoglou I, Strempfer J, Nelson CS, Hill JP, Chakhalian J, Bernhard C, Lang JC, Srajer G, Fukazawa H, Nakatsuji S, Maeno Y, Keimer B. Orbital ordering transition in Ca2RuO4 observed with resonant X-ray diffraction. PHYSICAL REVIEW LETTERS 2005; 95:136401. [PMID: 16197157 DOI: 10.1103/physrevlett.95.136401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2005] [Indexed: 05/04/2023]
Abstract
Resonant x-ray diffraction performed at the L(II) and L(III) absorption edges of Ru has been used to investigate the magnetic and orbital ordering in Ca2RuO4 single crystals. A large resonant enhancement due to electric dipole 2p-->4d transitions is observed at the wave-vector characteristic of antiferromagnetic ordering. Besides the previously known antiferromagnetic phase transition at T(N)=110 K, an additional phase transition, between two paramagnetic phases, is observed around 260 K. Based on the polarization and azimuthal angle dependence of the diffraction signal, this transition can be attributed to orbital ordering of the Ru t(2g) electrons. The propagation vector of the orbital order is inconsistent with some theoretical predictions for the orbital state of Ca2RuO4.
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Affiliation(s)
- I Zegkinoglou
- Max-Planck-Institut für Festkörperforschung, Stuttgart, Germany
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Kuepper K, Bondino F, Prince KC, Zangrando M, Zacchigna M, Takás AF, Crainic T, Matteucci M, Parmigiani F, Winiarski A, Galakhov VR, Mukovskii YM, Neumann M. Direct Investigation of Orbital Ordering in a Colossal Magnetoresistance Manganite by Means of X-ray Linear Dichroism at the Mn L Edge. J Phys Chem B 2005; 109:15667-70. [PMID: 16852985 DOI: 10.1021/jp052762s] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have investigated for the first time the orbital ordering in a three-dimensional colossal magnetoresistance manganite, namely La(7/8)Sr(1/8)MnO3, by applying soft X-ray linear dichroism (XLD) to the Mn L edge. We found that the cooperative Jahn-Teller distorted orthorhombic phase, which is present at a temperature of 240 K, is probably accompanied by a predominantly cross type (x2 - z2)/(y2 - z2) orbital ordering. This result is discussed in the light of different exchange interaction models.
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Thomas KJ, Hill JP, Grenier S, Kim YJ, Abbamonte P, Venema L, Rusydi A, Tomioka Y, Tokura Y, McMorrow DF, Sawatzky G, van Veenendaal M. Soft x-ray resonant diffraction study of magnetic and orbital correlations in a manganite near half doping. PHYSICAL REVIEW LETTERS 2004; 92:237204. [PMID: 15245194 DOI: 10.1103/physrevlett.92.237204] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2003] [Indexed: 05/24/2023]
Abstract
We have utilized resonant x-ray diffraction at the Mn L(II,III) edges in order to directly compare magnetic and orbital correlations in Pr0.6Ca0.4MnO3. Comparing the widths of the magnetic and orbital diffraction peaks, we find that the magnetic correlation length exceeds that of the orbital order by nearly a factor of 2. Furthermore, we observe a large (approximately 3 eV) spectral weight shift between the magnetic and orbital resonant line shapes, which cannot be explained within the classic Goodenough picture of a charge-ordered ground state. To explain the shift, we calculate the orbital and magnetic resonant diffraction line shapes based on a relaxed charge-ordered model.
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Affiliation(s)
- K J Thomas
- Department of Physics, Brookhaven National Laboratory, Upton, New York 11973, USA
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