1
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Aboljadayel ROM, Kinane CJ, Vaz CAF, Love DM, Martin MB, Cabrero-Vilatela A, Braeuninger-Weimer P, Ionescu A, Caruana AJ, Charlton TR, Llandro J, Monteiro PMDS, Barnes CHW, Hofmann S, Langridge S. Measurement of the Induced Magnetic Polarisation of Rotated-Domain Graphene Grown on Co Film with Polarised Neutron Reflectivity. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2620. [PMID: 37836260 PMCID: PMC10574451 DOI: 10.3390/nano13192620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 07/16/2023] [Accepted: 09/01/2023] [Indexed: 10/15/2023]
Abstract
In this paper, we determine the magnetic moment induced in graphene when grown on a cobalt film using polarised neutron reflectivity (PNR). A magnetic signal in the graphene was detected by X-ray magnetic circular dichroism (XMCD) spectra at the C K-edge. From the XMCD sum rules an estimated magnetic moment of 0.3 μB/C atom, while a more accurate estimation of 0.49 μB/C atom was obtained by carrying out a PNR measurement at 300 K. The results indicate that the higher magnetic moment in Co is counterbalanced by the larger lattice mismatch between the Co-C (1.6%) and the slightly longer bond length, inducing a magnetic moment in graphene that is similar to that reported in Ni/graphene heterostructures.
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Affiliation(s)
| | - Christy John Kinane
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
| | | | - David Michael Love
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, UK
| | | | | | | | - Adrian Ionescu
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, UK
| | - Andrew John Caruana
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
| | - Timothy Randall Charlton
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
| | - Justin Llandro
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, UK
| | | | | | - Stephan Hofmann
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK
| | - Sean Langridge
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, UK
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2
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Arguello Cruz E, Ducos P, Gao Z, Johnson ATC, Niebieskikwiat D. Exchange Coupling Effects on the Magnetotransport Properties of Ni-Nanoparticle-Decorated Graphene. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1861. [PMID: 37368291 DOI: 10.3390/nano13121861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 06/05/2023] [Accepted: 06/09/2023] [Indexed: 06/28/2023]
Abstract
We characterize the effect of ferromagnetic nickel nanoparticles (size ∼6 nm) on the magnetotransport properties of chemical-vapor-deposited (CVD) graphene. The nanoparticles were formed by thermal annealing of a thin Ni film evaporated on top of a graphene ribbon. The magnetoresistance was measured while sweeping the magnetic field at different temperatures, and compared against measurements performed on pristine graphene. Our results show that, in the presence of Ni nanoparticles, the usually observed zero-field peak of resistivity produced by weak localization is widely suppressed (by a factor of ∼3), most likely due to the reduction of the dephasing time as a consequence of the increase in magnetic scattering. On the other hand, the high-field magnetoresistance is amplified by the contribution of a large effective interaction field. The results are discussed in terms of a local exchange coupling, J∼6 meV, between the graphene π electrons and the 3d magnetic moment of nickel. Interestingly, this magnetic coupling does not affect the intrinsic transport parameters of graphene, such as the mobility and transport scattering rate, which remain the same with and without Ni nanoparticles, indicating that the changes in the magnetotransport properties have a purely magnetic origin.
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Affiliation(s)
- Erick Arguello Cruz
- Departamento de Fisica, Colegio de Ciencias e Ingenierias, Universidad San Francisco de Quito, Quito 170901, Ecuador
| | - Pedro Ducos
- Departamento de Fisica, Colegio de Ciencias e Ingenierias, Universidad San Francisco de Quito, Quito 170901, Ecuador
| | - Zhaoli Gao
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Alan T Charlie Johnson
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dario Niebieskikwiat
- Departamento de Fisica, Colegio de Ciencias e Ingenierias, Universidad San Francisco de Quito, Quito 170901, Ecuador
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3
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Aboljadayel ROM, Kinane CJ, Vaz CAF, Love DM, Weatherup RS, Braeuninger-Weimer P, Martin MB, Ionescu A, Caruana AJ, Charlton TR, Llandro J, Monteiro PMS, Barnes CHW, Hofmann S, Langridge S. Determining the Proximity Effect-Induced Magnetic Moment in Graphene by Polarized Neutron Reflectivity and X-ray Magnetic Circular Dichroism. ACS APPLIED MATERIALS & INTERFACES 2023; 15:22367-22376. [PMID: 37092734 PMCID: PMC10176321 DOI: 10.1021/acsami.2c02840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We report the magnitude of the induced magnetic moment in CVD-grown epitaxial and rotated-domain graphene in proximity with a ferromagnetic Ni film, using polarized neutron reflectivity (PNR) and X-ray magnetic circular dichroism (XMCD). The XMCD spectra at the C K-edge confirm the presence of a magnetic signal in the graphene layer, and the sum rules give a magnetic moment of up to ∼0.47 μB/C atom induced in the graphene layer. For a more precise estimation, we conducted PNR measurements. The PNR results indicate an induced magnetic moment of ∼0.41 μB/C atom at 10 K for epitaxial and rotated-domain graphene. Additional PNR measurements on graphene grown on a nonmagnetic Ni9Mo1 substrate, where no magnetic moment in graphene is measured, suggest that the origin of the induced magnetic moment is due to the opening of the graphene's Dirac cone as a result of the strong C pz-Ni 3d hybridization.
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Affiliation(s)
- Razan O M Aboljadayel
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Christy J Kinane
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, United Kingdom
| | - Carlos A F Vaz
- Swiss Light Source, Paul Scherrer Institut, Villigen PSI 5232, Switzerland
| | - David M Love
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Robert S Weatherup
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | | | - Marie-Blandine Martin
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | - Adrian Ionescu
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Andrew J Caruana
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, United Kingdom
| | - Timothy R Charlton
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, United Kingdom
| | - Justin Llandro
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Pedro M S Monteiro
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Crispin H W Barnes
- Cavendish Laboratory, Physics Department, University of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Stephan Hofmann
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
| | - Sean Langridge
- ISIS Facility, STFC Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Oxon OX11 0QX, United Kingdom
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4
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Guo Q, Ovcharenko R, Paulus B, Dedkov Y, Voloshina E. Electronic and Magnetic Properties of The Graphene/RE/Ni(111) (RE: La, Yb) Intercalation‐Like Interfaces: A DFT Analysis. ADVANCED THEORY AND SIMULATIONS 2022. [DOI: 10.1002/adts.202100621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Qilin Guo
- Department of Physics Shanghai University Shangda Road 99 Shanghai 200444 China
| | - Roman Ovcharenko
- Max‐Born‐Institut für Nichtlineare Optik und Kurzzeitspektroskopie Max‐Born‐Straße 2A Berlin 12489 Germany
| | - Beate Paulus
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 Berlin 14195 Germany
| | - Yuriy Dedkov
- Department of Physics Shanghai University Shangda Road 99 Shanghai 200444 China
- Centre of Excellence ENSEMBLE3 Sp.z o. o. Wolczynska Str. 133 Warsaw 01‐919 Poland
| | - Elena Voloshina
- Department of Physics Shanghai University Shangda Road 99 Shanghai 200444 China
- Institut für Chemie und Biochemie Freie Universität Berlin Arnimallee 22 Berlin 14195 Germany
- Centre of Excellence ENSEMBLE3 Sp.z o. o. Wolczynska Str. 133 Warsaw 01‐919 Poland
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5
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Jiang N, Bai Y, An H, Zhang H, Chen Y, He G, Zhao S. Sensitive angle-dependent magnetoelectric coupling in cluster-assembled flexible composites. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2022; 34:265301. [PMID: 35413706 DOI: 10.1088/1361-648x/ac66b4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
Flexible magnetoelectric (ME) device is one of the indispensable elements. However, the complicated fabrication process and low sensitivity hinder the practical applications. Here, flexible NiFe anisotropic magnetoelastic composites were prepared by cluster-supersonic expansion method assistant with polyvinylidene fluoride (PVDF) substrates. The NiFe/PVDF composites possess sensitive angle-resolution ME coupling coefficient at room temperature, and the value can reach 0.66μV deg-1. The strong anisotropic magnetoelasticity phenomenon is reminiscent of the short-range ordered cluster structure. The anisotropic magnetoelastic coefficient can be deduced by temperature- and magnetic field strength-dependent anisotropic magnetoresistance. The magnetic torque results also prove the strong anisotropic magnetoelastic trait. The coupling between piezoelectricity and anisotropic magnetostrictive effect endows great possibilities toward flexible electronic compass. These results shed light on future in non-invasive tracking of vital biological health via wearable electronic devices.
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Affiliation(s)
- Ning Jiang
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Yulong Bai
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Hengbin An
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Huatian Zhang
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Yongquan Chen
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Guixin He
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
| | - Shifeng Zhao
- Inner Mongolia Key Lab of Nanoscience and Nanotechnology, & School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, People's Republic of China
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6
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Wolf C, Delgado F, Reina J, Lorente N. Efficient Ab Initio Multiplet Calculations for Magnetic Adatoms on MgO. J Phys Chem A 2020; 124:2318-2327. [PMID: 32098473 DOI: 10.1021/acs.jpca.9b10749] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Scanning probe microscopy and spectroscopy, and more recently, single-atom electron spin resonance, have allowed the direct observation of electron dynamics at the atomic limit. The interpretation of data is strongly dependent on model Hamiltonians. However, fitting effective spin Hamiltonians to experimental data lacks the ability to explore a vast number of potential systems of interest. By using plane-wave density functional theory as starting point, we build a multiplet Hamiltonian making use of maximally localized Wannier functions. The Hamiltonian contains spin-orbit and electron-electron interactions needed to obtain the relevant spin dynamics. The resulting reduced Hamiltonian is solved by exact diagonalization. We compare three prototypical cases of 3d transition metals Mn (total spin S = 5/2), Fe (S = 2), and Co (S = 3/2) on MgO with experimental data and find that our calculations can accurately predict the spin orientation and anisotropy of the magnetic adatom. Our method does not rely on experimental input and allows us to explore and predict the fundamental magnetic properties of adatoms on surfaces.
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Affiliation(s)
- Christoph Wolf
- Center for Quantum Nanoscience, Institute for Basic Science (IBS), Seoul 03760, Republic of Korea.,Ewha Womans University, Seoul 03760, Republic of Korea
| | - Fernando Delgado
- Instituto de estudios avanzados IUDEA, Departamento de Fı́sica, Universidad de La Laguna, 38203 Tenerife, Spain
| | - José Reina
- Centro de Fı́sica de Materiales, Centro Mixto CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, E-20018 Donostia-San Sebastián, Spain
| | - Nicolás Lorente
- Centro de Fı́sica de Materiales, Centro Mixto CSIC-UPV/EHU, Paseo Manuel de Lardizabal 5, E-20018 Donostia-San Sebastián, Spain
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7
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Andersen HL, Saura-Múzquiz M, Granados-Miralles C, Canévet E, Lock N, Christensen M. Crystalline and magnetic structure-property relationship in spinel ferrite nanoparticles. NANOSCALE 2018; 10:14902-14914. [PMID: 30044457 DOI: 10.1039/c8nr01534a] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Magnetic spinel ferrite MFe2O4 (M = Mn, Co, Ni, Zn) nanoparticles have been prepared via simple, green and scalable hydrothermal synthesis pathways utilizing sub- and supercritical conditions to attain specific product characteristics. The crystal-, magnetic- and micro-structures of the prepared crystallites have been elucidated through meticulous characterization employing several complementary techniques. Analysis of energy dispersive X-ray spectroscopy (EDS) and X-ray absorption near edge structure (XANES) data verifies the desired stoichiometries with divalent M and trivalent Fe ions. Robust structural characterization is carried out by simultaneous Rietveld refinement of a constrained structural model to powder X-ray diffraction (PXRD) and high-resolution neutron powder diffraction (NPD) data. The structural modeling reveals different affinities of the 3d transition metal ions for the specific crystallographic sites in the nanocrystallites, characterized by the spinel inversion degree, x, [M2+1-xFe3+x]tet[M2+xFe3+2-x]octO4, compared to the well-established bulk structures. The MnFe2O4 and CoFe2O4 nanocrystallites exhibit random disordered spinel structures (x = 0.643(3) and 0.660(6)), while NiFe2O4 is a completely inverse spinel (x = 1.00) and ZnFe2O4 is close to a normal spinel (x = 0.166(10)). Furthermore, the size, size distribution and morphology of the nanoparticles have been assessed by peak profile analysis of the diffraction data, transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The differences in nanostructure, spinel inversion and distinct magnetic nature of the M2+ ions directly alter the magnetic structures of the crystallites at the atomic-scale and consequently the macroscopic magnetic properties of the materials. The present study serves as an important structural benchmark for the rapidly expanding field of spinel ferrite nanoparticle research.
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Affiliation(s)
- Henrik Lyder Andersen
- Center for Materials Crystallography, Department of Chemistry and Interdisciplinary Nanoscience Centre (iNANO), Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark.
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8
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Wang H, Friedrich S, Li L, Mao Z, Ge P, Balasubramanian M, Patil DS. L-edge sum rule analysis on 3d transition metal sites: from d 10 to d 0 and towards application to extremely dilute metallo-enzymes. Phys Chem Chem Phys 2018; 20:8166-8176. [PMID: 29521394 PMCID: PMC5895852 DOI: 10.1039/c7cp06624d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
According to L-edge sum rules, the number of 3d vacancies at a transition metal site is directly proportional to the integrated intensity of the L-edge X-ray absorption spectrum (XAS) for the corresponding metal complex. In this study, the numbers of 3d holes are characterized quantitatively or semi-quantitatively for a series of manganese (Mn) and nickel (Ni) complexes, including the electron configurations 3d10→ 3d0. In addition, extremely dilute (<0.1% wt/wt) Ni enzymes were examined by two different approaches: (1) by using a high resolution superconducting tunnel junction X-ray detector to obtain XAS spectra with a very high signal-to-noise ratio, especially in the non-variant edge jump region; and (2) by adding an inert tracer to the sample that provides a prominent spectral feature to replace the weak edge jump for intensity normalization. In this publication, we present for the first time: (1) L-edge sum rule analysis for a series of Mn and Ni complexes that include electron configurations from an open shell 3d0 to a closed shell 3d10; (2) a systematic analysis on the uncertainties, especially on that from the edge jump, which was missing in all previous reports; (3) a clearly-resolved edge jump between pre-L3 and post-L2 regions from an extremely dilute sample; (4) an evaluation of an alternative normalization standard for L-edge sum rule analysis. XAS from two copper (Cu) proteins measured using a conventional semiconductor X-ray detector are also repeated as bridges between Ni complexes and dilute Ni enzymes. The differences between measuring 1% Cu enzymes and measuring <0.1% Ni enzymes are compared and discussed. This study extends L-edge sum rule analysis to virtually any 3d metal complex and any dilute biological samples that contain 3d metals.
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Affiliation(s)
- Hongxin Wang
- Department of Chemistry, University of California, Davis, CA 95616, USA. and Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Stephan Friedrich
- Lawrence Livermore National Laboratory, Advanced Detectors Group, 7000 East Avenue, Livermore, CA 94550, USA
| | - Lei Li
- Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2 Kouto, Shingu-cho, Tatsuno, Hyogo 679-5165, Japan
| | - Ziliang Mao
- Department of Chemistry, University of California, Davis, CA 95616, USA.
| | - Pinghua Ge
- Department of Physics, University of Illinois, 1110 West Green St., Urbana, IL 61801, USA
| | | | - Daulat S Patil
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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9
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Patrick CE, Kumar S, Balakrishnan G, Edwards RS, Lees MR, Petit L, Staunton JB. Calculating the Magnetic Anisotropy of Rare-Earth-Transition-Metal Ferrimagnets. PHYSICAL REVIEW LETTERS 2018; 120:097202. [PMID: 29547338 DOI: 10.1103/physrevlett.120.097202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Indexed: 06/08/2023]
Abstract
Magnetocrystalline anisotropy, the microscopic origin of permanent magnetism, is often explained in terms of ferromagnets. However, the best performing permanent magnets based on rare earths and transition metals (RE-TM) are in fact ferrimagnets, consisting of a number of magnetic sublattices. Here we show how a naive calculation of the magnetocrystalline anisotropy of the classic RE-TM ferrimagnet GdCo_{5} gives numbers that are too large at 0 K and exhibit the wrong temperature dependence. We solve this problem by introducing a first-principles approach to calculate temperature-dependent magnetization versus field (FPMVB) curves, mirroring the experiments actually used to determine the anisotropy. We pair our calculations with measurements on a recently grown single crystal of GdCo_{5}, and find excellent agreement. The FPMVB approach demonstrates a new level of sophistication in the use of first-principles calculations to understand RE-TM magnets.
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Affiliation(s)
| | - Santosh Kumar
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Geetha Balakrishnan
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Rachel S Edwards
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Martin R Lees
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Leon Petit
- Daresbury Laboratory, Daresbury, Warrington WA4 4AD, United Kingdom
| | - Julie B Staunton
- Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom
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10
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Akin ST, Zamudio-Bayer V, Duanmu K, Leistner G, Hirsch K, Bülow C, Ławicki A, Terasaki A, Issendorff BV, Truhlar DG, Lau JT, Duncan MA. Size-Dependent Ligand Quenching of Ferromagnetism in Co 3(benzene) n+ Clusters Studied with X-ray Magnetic Circular Dichroism Spectroscopy. J Phys Chem Lett 2016; 7:4568-4575. [PMID: 27779876 DOI: 10.1021/acs.jpclett.6b01839] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Cobalt-benzene cluster ions of the form Co3(bz)n+ (n = 0-3) were produced in the gas phase, mass-selected, and cooled in a cryogenic ion trap held at 3-4 K. To explore ligand effects on cluster magnetic moments, these species were investigated with X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) spectroscopy. XMCD spectra yield both the spin and orbital angular momenta of these clusters. Co3+ has a spin magnetic moment of μS = 6 μB and an orbital magnetic moment of μL = 3 μB. Co3(bz)+ and Co3(bz)2+ complexes were found to have spin and orbital magnetic moments identical to the values for ligand-free Co3+. However, coordination of the third benzene to form Co3(bz)3+ completely quenches the high spin state of the system. Density functional theory calculations elucidate the spin states of the Co3(bz)n+ species as a function of the number of attached benzene ligands, explaining the transition from septet to singlet for n = 0 → 3.
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Affiliation(s)
- Scott T Akin
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Vicente Zamudio-Bayer
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Physikalisches Institut, Universität Freiburg , Stefan-Meier-Straße 21, 79104 Freiburg, Germany
| | - Kaining Duanmu
- Department of Chemistry, Chemical Theory Center, and the Supercomputing Institute, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - Georg Leistner
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany
| | - Konstantin Hirsch
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany
| | - Christine Bülow
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin , Hardenbergstraße 36, 10623 Berlin, Germany
| | - Arkadiusz Ławicki
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - Akira Terasaki
- East Tokyo Laboratory, Genesis Research Institute, Inc. , 717-86 Futamata, Ichikawa, Chiba 272-0001, Japan
- Department of Chemistry, Faculty of Science, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Bernd von Issendorff
- Physikalisches Institut, Universität Freiburg , Stefan-Meier-Straße 21, 79104 Freiburg, Germany
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and the Supercomputing Institute, University of Minnesota , Minneapolis, Minnesota 55455, United States
| | - J Tobias Lau
- Institut für Methoden und Instrumentierung der Forschung mit Synchrotronstrahlung, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Straße 15, 12489 Berlin, Germany
| | - Michael A Duncan
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
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11
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Magnetism and exchange interaction of small rare-earth clusters; Tb as a representative. Sci Rep 2016; 6:19676. [PMID: 26795239 PMCID: PMC4726341 DOI: 10.1038/srep19676] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2015] [Accepted: 09/24/2015] [Indexed: 01/08/2023] Open
Abstract
Here we follow, both experimentally and theoretically, the development of magnetism in Tb clusters from the atomic limit, adding one atom at a time. The exchange interaction is, surprisingly, observed to drastically increase compared to that of bulk, and to exhibit irregular oscillations as a function of the interatomic distance. From electronic structure theory we find that the theoretical magnetic moments oscillate with cluster size in exact agreement with experimental data. Unlike the bulk, the oscillation is not caused by the RKKY mechanism. Instead, the inter-atomic exchange is shown to be driven by a competition between wave-function overlap of the 5d shell and the on-site exchange interaction, which leads to a competition between ferromagnetic double-exchange and antiferromagnetic super-exchange. This understanding opens up new ways to tune the magnetic properties of rare-earth based magnets with nano-sized building blocks.
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12
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Baumann S, Donati F, Stepanow S, Rusponi S, Paul W, Gangopadhyay S, Rau IG, Pacchioni GE, Gragnaniello L, Pivetta M, Dreiser J, Piamonteze C, Lutz CP, Macfarlane RM, Jones BA, Gambardella P, Heinrich AJ, Brune H. Origin of Perpendicular Magnetic Anisotropy and Large Orbital Moment in Fe Atoms on MgO. PHYSICAL REVIEW LETTERS 2015; 115:237202. [PMID: 26684139 DOI: 10.1103/physrevlett.115.237202] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Indexed: 06/05/2023]
Abstract
We report on the magnetic properties of individual Fe atoms deposited on MgO(100) thin films probed by x-ray magnetic circular dichroism and scanning tunneling spectroscopy. We show that the Fe atoms have strong perpendicular magnetic anisotropy with a zero-field splitting of 14.0±0.3 meV/atom. This is a factor of 10 larger than the interface anisotropy of epitaxial Fe layers on MgO and the largest value reported for Fe atoms adsorbed on surfaces. The interplay between the ligand field at the O adsorption sites and spin-orbit coupling is analyzed by density functional theory and multiplet calculations, providing a comprehensive model of the magnetic properties of Fe atoms in a low-symmetry bonding environment.
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Affiliation(s)
- S Baumann
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
- Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - F Donati
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - S Stepanow
- Department of Materials, ETH Zürich, Hönggerbergring 64, CH-8093 Zürich, Switzerland
| | - S Rusponi
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - W Paul
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - S Gangopadhyay
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
- Department of Physics, University of California, Davis, California 95616, USA
| | - I G Rau
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - G E Pacchioni
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - L Gragnaniello
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - M Pivetta
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - J Dreiser
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - C Piamonteze
- Swiss Light Source (SLS), Paul Scherrer Institute (PSI), CH-5232 Villigen PSI, Switzerland
| | - C P Lutz
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - R M Macfarlane
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - B A Jones
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - P Gambardella
- Department of Materials, ETH Zürich, Hönggerbergring 64, CH-8093 Zürich, Switzerland
| | - A J Heinrich
- IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, USA
| | - H Brune
- Institute of Condensed Matter Physics, École Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
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13
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Shiozawa H, Briones-Leon A, Domanov O, Zechner G, Sato Y, Suenaga K, Saito T, Eisterer M, Weschke E, Lang W, Peterlik H, Pichler T. Nickel clusters embedded in carbon nanotubes as high performance magnets. Sci Rep 2015; 5:15033. [PMID: 26459370 PMCID: PMC4602218 DOI: 10.1038/srep15033] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 08/28/2015] [Indexed: 11/15/2022] Open
Abstract
Ensembles of fcc nickel nanowires have been synthesized with defined mean sizes in the interior of single-wall carbon nanotubes. The method allows the intrinsic nature of single-domain magnets to emerge with large coercivity as their size becomes as small as the exchange length of nickel. By means of X-ray magnetic circular dichroism we probe electronic interactions at nickel-carbon interfaces where nickel exhibit no hysteresis and size-dependent spin magnetic moment. A manifestation of the interacting two subsystems on a bulk scale is traced in the nanotube’s magnetoresistance as explained within the framework of weak localization.
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Affiliation(s)
- Hidetsugu Shiozawa
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Antonio Briones-Leon
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Oleg Domanov
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Georg Zechner
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Yuta Sato
- Nanomaterials Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Kazu Suenaga
- Nanomaterials Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | - Takeshi Saito
- Nanomaterials Research Institute, AIST, 1-1-1 Higashi, Tsukuba 305-8565, Japan
| | | | - Eugen Weschke
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - Wolfgang Lang
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Herwig Peterlik
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Thomas Pichler
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
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14
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Fang YW, Ding HC, Tong WY, Zhu WJ, Shen X, Gong SJ, Wan XG, Duan CG. First-principles studies of multiferroic and magnetoelectric materials. Sci Bull (Beijing) 2015. [DOI: 10.1007/s11434-014-0628-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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15
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Gu W, Wang H, Wang K. Nickel L-edge and K-edge X-ray absorption spectroscopy of non-innocent Ni[S₂C₂(CF₃)₂]₂(n) series (n = -2, -1, 0): direct probe of nickel fractional oxidation state changes. Dalton Trans 2014; 43:6406-13. [PMID: 24604143 DOI: 10.1039/c4dt00308j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of nickel dithiolene complexes Ni[S2C2(CF3)2]2(n) (n = -2, -1, 0) has been investigated using Ni L- and K-edge X-ray absorption spectroscopy (XAS). The L3 centroid shifts about 0.3 eV for a change of one unit in the formal oxidation state (or 0.3 eV per oxi), corresponding to ~33% of the shift for Ni oxides or fluorides (about 0.9 eV per oxi). The K-edge XAS edge position shifts about 0.7 eV per oxi, corresponding to ~38% of that for Ni oxides (1.85 eV per oxi). In addition, Ni L sum rule analysis found the Ni(3d) ionicity in the frontier orbitals being 50.5%, 44.0% and 38.5% respectively (for n = -2, -1, 0), in comparison with their formal oxidation states (of Ni(II), Ni(III), and Ni(IV)). For the first time, direct and quantitative measurement of the Ni fractional oxidation state changes becomes possible for Ni dithiolene complexes, illustrating the power of L-edge XAS and L sum rule analysis in such a study. The Ni L-edge and K-edge XAS can be used in a complementary manner to better assess the oxidation states for Ni.
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Affiliation(s)
- Weiwei Gu
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.
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16
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Rau IG, Baumann S, Rusponi S, Donati F, Stepanow S, Gragnaniello L, Dreiser J, Piamonteze C, Nolting F, Gangopadhyay S, Albertini OR, Macfarlane RM, Lutz CP, Jones BA, Gambardella P, Heinrich AJ, Brune H. Reaching the magnetic anisotropy limit of a 3d metal atom. Science 2014; 344:988-92. [PMID: 24812206 DOI: 10.1126/science.1252841] [Citation(s) in RCA: 269] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Designing systems with large magnetic anisotropy is critical to realize nanoscopic magnets. Thus far, the magnetic anisotropy energy per atom in single-molecule magnets and ferromagnetic films remains typically one to two orders of magnitude below the theoretical limit imposed by the atomic spin-orbit interaction. We realized the maximum magnetic anisotropy for a 3d transition metal atom by coordinating a single Co atom to the O site of an MgO(100) surface. Scanning tunneling spectroscopy reveals a record-high zero-field splitting of 58 millielectron volts as well as slow relaxation of the Co atom's magnetization. This striking behavior originates from the dominating axial ligand field at the O adsorption site, which leads to out-of-plane uniaxial anisotropy while preserving the gas-phase orbital moment of Co, as observed with x-ray magnetic circular dichroism.
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Affiliation(s)
- Ileana G Rau
- IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA
| | - Susanne Baumann
- IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA. Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland
| | - Stefano Rusponi
- Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - Fabio Donati
- Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - Sebastian Stepanow
- Department of Materials, Eidgenössische Technische Hochschule (ETH) Zürich, Hönggerbergring 64, CH-8093 Zürich, Switzerland
| | - Luca Gragnaniello
- Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland
| | - Jan Dreiser
- Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland. Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Cinthia Piamonteze
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | - Frithjof Nolting
- Swiss Light Source, Paul Scherrer Institute, CH-5232 Villigen PSI, Switzerland
| | | | - Oliver R Albertini
- IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA. Department of Physics, Georgetown University, 3700 O Street NW, Washington, DC 20057, USA
| | | | | | - Barbara A Jones
- IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120, USA
| | - Pietro Gambardella
- Department of Materials, Eidgenössische Technische Hochschule (ETH) Zürich, Hönggerbergring 64, CH-8093 Zürich, Switzerland.
| | | | - Harald Brune
- Institute of Condensed Matter Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 3, CH-1015 Lausanne, Switzerland.
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17
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Bezerra-Neto MM, Ribeiro MS, Sanyal B, Bergman A, Muniz RB, Eriksson O, Klautau AB. Complex magnetic structure of clusters and chains of Ni and Fe on Pt(111). Sci Rep 2013; 3:3054. [PMID: 24165828 PMCID: PMC3810666 DOI: 10.1038/srep03054] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 09/13/2013] [Indexed: 11/30/2022] Open
Abstract
We present an approach to control the magnetic structure of adatoms adsorbed on a substrate having a high magnetic susceptibility. Using finite Ni-Pt and Fe-Pt nanowires and nanostructures on Pt(111) surfaces, our ab initio results show that it is possible to tune the exchange interaction and magnetic configuration of magnetic adatoms (Fe or Ni) by introducing different numbers of Pt atoms to link them, or by including edge effects. The exchange interaction between Ni (or Fe) adatoms on Pt(111) can be considerably increased by introducing Pt chains to link them. The magnetic ordering can be regulated allowing for ferromagnetic or antiferromagnetic configurations. Noncollinear magnetic alignments can also be stabilized by changing the number of Pt-mediated atoms. An Fe-Pt triangularly-shaped nanostructure adsorbed on Pt(111) shows the most complex magnetic structure of the systems considered here: a spin-spiral type of magnetic order that changes its propagation direction at the triangle vertices.
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18
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Bordel C, Juraszek J, Cooke DW, Baldasseroni C, Mankovsky S, Minár J, Ebert H, Moyerman S, Fullerton EE, Hellman F. Fe spin reorientation across the metamagnetic transition in strained FeRh thin films. PHYSICAL REVIEW LETTERS 2012; 109:117201. [PMID: 23005667 DOI: 10.1103/physrevlett.109.117201] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Indexed: 06/01/2023]
Abstract
A spin reorientation accompanying the temperature-induced antiferromagnetic (AFM) to ferromagnetic (FM) phase transition is reported in strained epitaxial FeRh thin films. (57)Fe conversion electron Mössbauer spectrometry showed that the Fe moments have different orientations in FeRh grown on thick single-crystalline MgO and in FeRh grown on ion-beam-assist-deposited (IBAD) MgO. It was also observed, in both samples, that the Fe moments switch orientations at the AFM to FM phase transition. Perpendicular anisotropy was evidenced in the AFM phase of the film grown on IBAD MgO and in the FM phase of that grown on regular MgO. Density-functional theory calculations enabled this spin-reorientation transition to be accurately reproduced for both FeRh films across the AFM-FM phase transition and show that these results are due to differences in strain.
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Affiliation(s)
- C Bordel
- Department of Physics, University of California, Berkeley, Berkeley, California 94720, USA
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19
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Torchio R, Kvashnin YO, Pascarelli S, Mathon O, Marini C, Genovese L, Bruno P, Garbarino G, Dewaele A, Occelli F, Loubeyre P. X-ray magnetic circular dichroism measurements in Ni up to 200 GPa: resistant ferromagnetism. PHYSICAL REVIEW LETTERS 2011; 107:237202. [PMID: 22182121 DOI: 10.1103/physrevlett.107.237202] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Indexed: 05/31/2023]
Abstract
The structural stability of fcc Ni over a very large pressure range offers a unique opportunity to experimentally investigate how magnetism is modified by simple compression. K-edge x-ray magnetic circular dichroism (XMCD) shows that fcc Ni is ferromagnetic up to 200 GPa, contradicting recent predictions of an abrupt transition to a paramagnetic state at 160 GPa. Density functional theory calculations point out that the pressure evolution of the K-edge XMCD closely follows that of the p projected orbital moment rather than that of the total spin moment. The disappearance of magnetism in Ni is predicted to occur above 400 GPa.
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Affiliation(s)
- R Torchio
- European Synchrotron Radiation Facility, 6 Rue Jules Horowitz, BP220, 38043 Grenoble Cedex, France
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20
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Lyubina J, Rellinghaus B, Gutfleisch O, Albrecht M. Structure and Magnetic Properties of L10-Ordered Fe–Pt Alloys and Nanoparticles. HANDBOOK OF MAGNETIC MATERIALS 2011. [DOI: 10.1016/b978-0-444-53780-5.00005-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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21
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Klautau AB, Socolovsky LM, Nogueira RN, Petrilli HM. Hyperfine and magnetic properties of Fe-Cu clusters and Fe precipitates embedded in a Cu matrix. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2009; 21:506001. [PMID: 21836226 DOI: 10.1088/0953-8984/21/50/506001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Using the first-principles real-space linear muffin-tin orbital method within the atomic sphere approximation (RS-LMTO-ASA) we study hyperfine and local magnetic properties of substituted pure Fe and Fe-Cu clusters in an fcc Cu matrix. Spin and orbital contributions to magnetic moments, hyperfine fields and the Mössbauer isomer shifts at the Fe sites in Fe precipitates and Fe-Cu alloy clusters of sizes up to 60 Fe atoms embedded in the Cu matrix are calculated and the influence of the local environment on these properties is discussed.
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Affiliation(s)
- A B Klautau
- Faculdade de Física, Universidade Federal do Pará, 66075-110, Belém, PA, Brazil
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22
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Muñoz-Navia M, Dorantes-Dávila J, Zitoun D, Amiens C, Chaudret B, Casanove MJ, Lecante P, Jaouen N, Rogalev A, Respaud M, Pastor GM. Magnetic properties of CoNRhMnanoparticles: experiment and theory. Faraday Discuss 2008; 138:181-92; discussion 211-23, 433-4. [DOI: 10.1039/b705122k] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Brewer WD, Scherz A, Sorg C, Wende H, Baberschke K, Bencok P, Frota-Pessôa S. Direct observation of orbital magnetism in cubic solids. PHYSICAL REVIEW LETTERS 2004; 93:077205. [PMID: 15324272 DOI: 10.1103/physrevlett.93.077205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2003] [Indexed: 05/24/2023]
Abstract
We present x-ray magnetic circular dichroism determinations of the orbital/spin magnetic moment ratios of dilute 3d-series impurities in Au (and Cu) host matrices. This is the first direct measurement of considerable orbital moments in cubic symmetry for a localized impurity in a bulk metal host. It is shown that the unquenching of orbital magnetism depends on a delicate balance of hybridization effects between the local impurity with the host and the filling of the 3d states of the impurity. The results are accompanied by ab initio calculations that support our experimental findings.
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Affiliation(s)
- W D Brewer
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin-Dahlem, Germany.
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24
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Eschrig H, Richter M, Opahle I. Relativistic Solid State Calculations. THEORETICAL AND COMPUTATIONAL CHEMISTRY 2004. [DOI: 10.1016/s1380-7323(04)80039-6] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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25
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Ground- and excited-state properties of inorganic solids from full-potential density-functional calculations. J SOLID STATE CHEM 2003. [DOI: 10.1016/s0022-4596(03)00215-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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26
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27
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Wang H, Ge P, Riordan CG, Brooker S, Woomer CG, Collins T, Melendres CA, Graudejus O, Bartlett N, Cramer SP. Integrated X-ray L Absorption Spectra. Counting Holes in Ni Complexes. J Phys Chem B 1998. [DOI: 10.1021/jp9821026] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hongxin Wang
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - Pinghua Ge
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - C. G. Riordan
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - S. Brooker
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - C. G. Woomer
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - T. Collins
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - C. A. Melendres
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - O. Graudejus
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - N. Bartlett
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
| | - S. P. Cramer
- Department of Applied Science, University of California, Davis, California 95616, Structural Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand, Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, Materials Science and Chemical Technology Division, Argonne National
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28
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Iwashita K, Oguchi T, Jo T. Orbital and spin magnetic moments of TPt3 (T=V, Cr, Mn, Fe, and Co). PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 54:1159-1162. [PMID: 9985386 DOI: 10.1103/physrevb.54.1159] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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29
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Daalderop GH, Kelly PJ, Schuurmans MF. Magnetocrystalline anisotropy of YCo5 and related RECo5 compounds. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:14415-14433. [PMID: 9983240 DOI: 10.1103/physrevb.53.14415] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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30
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Hjortstam O, Trygg J, Wills JM, Johansson B, Eriksson O. Calculated spin and orbital moments in the surfaces of the 3d metals Fe, Co, and Ni and their overlayers on Cu(001). PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:9204-9213. [PMID: 9982422 DOI: 10.1103/physrevb.53.9204] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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31
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Igarashi J, Hirai K. Orbital moment and magnetic circular dichroism at the K edge in ferromagnetic cobalt. PHYSICAL REVIEW. B, CONDENSED MATTER 1996; 53:6442-6450. [PMID: 9982043 DOI: 10.1103/physrevb.53.6442] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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32
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Kulakowski K. Model calculation of two-ion magnetostriction in the itinerant uniaxial ferromagnet Y2Fe17. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:15943-15950. [PMID: 9980973 DOI: 10.1103/physrevb.52.15943] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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33
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Weller D, Stöhr J, Nakajima R, Carl A, Samant MG, Chappert C, Mégy R, Beauvillain P, Veillet P, Held GA. Microscopic origin of magnetic anisotropy in Au/Co/Au probed with x-ray magnetic circular dichroism. PHYSICAL REVIEW LETTERS 1995; 75:3752-3755. [PMID: 10059718 DOI: 10.1103/physrevlett.75.3752] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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34
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Stöhr J, König H. Determination of spin- and orbital-moment anisotropies in transition metals by angle-dependent x-ray magnetic circular dichroism. PHYSICAL REVIEW LETTERS 1995; 75:3748-3751. [PMID: 10059717 DOI: 10.1103/physrevlett.75.3748] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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35
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Tobin JG, Waddill GD, Jankowski AF, Sterne PA, Pappas DP. Comparison of branching ratio and sum-rule analyses of magnetic circular dichroism in x-ray-absorption spectroscopy. PHYSICAL REVIEW. B, CONDENSED MATTER 1995; 52:6530-6541. [PMID: 9981882 DOI: 10.1103/physrevb.52.6530] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Igarashi J, Hirai K. Magnetic circular dichroism at the K edge of nickel and iron. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:17820-17829. [PMID: 9976215 DOI: 10.1103/physrevb.50.17820] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Kulakowski K. Model calculation of the crystal-field magnetostriction and its temperature dependence in the itinerant uniaxial ferromagnet Y2Fe17. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 50:234-241. [PMID: 9974536 DOI: 10.1103/physrevb.50.234] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Weller D, Wu Y, Stöhr J, Samant MG, Hermsmeier BD, Chappert C. Orbital magnetic moments of Co in multilayers with perpendicular magnetic anisotropy. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:12888-12896. [PMID: 10010198 DOI: 10.1103/physrevb.49.12888] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Böske T, Clemens W, Carbone C, Eberhardt W. Circular magnetic x-ray dichroism of 3d impurities in Ni. PHYSICAL REVIEW. B, CONDENSED MATTER 1994; 49:4003-4009. [PMID: 10011296 DOI: 10.1103/physrevb.49.4003] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Severin L, Brooks MS, Johansson B. Relationship between the Coulomb integral U and the Stoner parameter I. PHYSICAL REVIEW LETTERS 1993; 71:3214-3217. [PMID: 10054886 DOI: 10.1103/physrevlett.71.3214] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Hjelm A, Calais JL. Self-consistent calculations of the Zeeman splitting in metals. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:8592-8606. [PMID: 10007073 DOI: 10.1103/physrevb.48.8592] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Thole BT. Spin polarization and magnetic dichroism in photoemission from core and valence states in localized magnetic systems. II. Emission from open shells. PHYSICAL REVIEW. B, CONDENSED MATTER 1993; 48:210-223. [PMID: 10006767 DOI: 10.1103/physrevb.48.210] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Chapter 112 Theory of cohesion in rare earths and actinides. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/s0168-1273(05)80029-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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Franse J, Radwański R. Chapter 5 Magnetic properties of binary rare-earth 3d-transition-metal intermetallic compounds. HANDBOOK OF MAGNETIC MATERIALS 1993. [DOI: 10.1016/s1567-2719(05)80046-0] [Citation(s) in RCA: 99] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Chapter 3 Density functional theory of the ground-state magnetic properties of rare earths and actinides. HANDBOOK OF MAGNETIC MATERIALS 1993. [DOI: 10.1016/s1567-2719(05)80044-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Hoyland MA, Surman M, Flipse CF, Thole BT. Surface orbital magnetic moment of ferromagnetic nickel studied by magnetic circular dichroism in Ni3p core level photoemission. PHYSICAL REVIEW LETTERS 1992; 69:3827-3830. [PMID: 10046924 DOI: 10.1103/physrevlett.69.3827] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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McMullan GJ, Pilgram DD, Marshall A. Fermi surface and band structure of ferromagnetic cobalt. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:3789-3797. [PMID: 10004102 DOI: 10.1103/physrevb.46.3789] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Smith NV, Chen CT, Sette F, Mattheiss LF. Relativistic tight-binding calculations of x-ray absorption and magnetic circular dichroism at the L2 and L3 edges of nickel and iron. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 46:1023-1032. [PMID: 10003290 DOI: 10.1103/physrevb.46.1023] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Söderlind P, Eriksson O, Johansson B, Albers RC, Boring AM. Spin and orbital magnetism in Fe-Co and Co-Ni alloys. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:12911-12916. [PMID: 10001354 DOI: 10.1103/physrevb.45.12911] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Qi Q, Sun H, Skomski R, Coey JM. Magnetization and 57Fe hyperfine fields in Y2Fe17Z3- delta (Z=H, C, or N) interstitial compounds. PHYSICAL REVIEW. B, CONDENSED MATTER 1992; 45:12278-12286. [PMID: 10001263 DOI: 10.1103/physrevb.45.12278] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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