174 citations · 1.3k across the 24 of their papers we have counts for
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Quantitative study of the f occupation in CeMIn5 and other cerium compounds with hard x-rays
M. Sundermann, F. Strigari, T. Willers +19
We present bulk-sensitive hard x-ray photoelectron spectroscopy (HAXPES) data of the Ce3d core levels and lifetime-reduced L edge x-ray absorption spectroscopy (XAS) in the partial…
Electronic and Spin States of SrRuO3 Thin Films: an X-ray Magnetic Circular Dichroism Study
S. Agrestini, Z. Hu, C. -Y. Kuo +14
We report a study of the local magnetism in thin films of SrRuO3 grown on (111) and (001) oriented SrTiO3 substrates using x-ray magnetic circular dichroism spectroscopy (XMCD) at…
Spectroscopic evidence for giant orbital moment and magnetic anisotropy induced by local distortions in alpha-CoV2O6
N. Hollmann, S. Agrestini, Z. Hu +9
We present a combined experimental and theoretical study on the local magnetism of the Co ions in the spin-chain compound CoV2O6, which crystallizes in two different allotropic pha…
Correlation effects in CaCu3Ru4O12
N. Hollmann, Z. Hu, A. Maignan +7
We have investigated the electronic structure of CaCu3Ru4O12 and LaCu3Ru4O12 using soft x-ray photoelectron and absorption spectroscopy together with band structure and cluster con…
Evidence for a temperature-induced spin-state transition of Co3+ in La2-xSrxCoO4
N. Hollmann, M. W. Haverkort, M. Benomar +3
We study the magnetic susceptibility of mixed-valent La2-xSrxCoO4 single crystals in the doping range of 0.5<= x <= 0.8 for temperatures up to 1000 K. The magnetism below room temp…
Insulator-Metal Transition in TiGePt: a combined photoelectron spectroscopy, x-ray absorption spectroscopy, and band structure study
J. Gegner, M. Gamza, S. -V. Ackerbauer +10
We present a combined experimental and theoretical study of the electronic structure of the intermetallic compound TiGePt by means of photoelectron spectroscopy, x-ray absorption s…
From antiferromagnetic insulator to correlated metal in pressurized and doped LaMnPO
J. W. Simonson, Z. P. Yin, M. Pezzoli +17
Widespread adoption of superconducting technologies requires the discovery of new materials with enhanced properties, especially higher superconducting transition temperatures T$_{…
Orbital order in La0.5Sr1.5MnO4: beyond a common local Jahn-Teller picture
Hua Wu, C. F. Chang, O. Schumann +9
The standard way to find the orbital occupation of Jahn-Teller (JT) ions is to use structural data, with the assumption of a one-to-one correspondence between the orbital occupatio…
Nature of magnetic order in YbInNi4
T. Willers, N. Hollmann, S. Wirth +4
We have measured field and temperature dependent magnetization of YbInNi4 to elucidate the nature of the magnetic transition at 3 K. For small fields we find magnetic order as prev…
Orbital occupation and magnetic moments of tetrahedrally coordinated iron in CaBaFe4O7
N. Hollmann, Z. Hu, Hua Wu +8
CaBaFe4O7 is a mixed-valent transition metal oxide having both Fe2+ and Fe3+ ions in tetrahedral coordination. Here we characterize its magnetic properties by magnetization measure…
Local symmetry and magnetic anisotropy in multiferroic MnWO4 and antiferromagnetic CoWO4 studied by soft x-ray absorption spectroscopy
N. Hollmann, Z. Hu, T. Willers +7
Soft x-ray absorption experiments on the transition metal L2,3 edge of multiferroic MnWO4 and antiferromagnetic CoWO4 are presented. The observed linear polarization dependence, an…
Crystal-field and Kondo scale investigation of CeMIn5 (M=Co, Ir and Rh): a combined x-ray absorption and inelastic neutron study
T. Willers, Z. Hu, N. Hollmann +15
Linear polarized soft-x ray absorption (XAS) and inelastic neutron scattering (INS) experiments have been performed on CeMIn5 with M = Rh, Ir, and Co to determine the crystal-field…
Symmetry analysis of magneto-optical effects: The case of x-ray diffraction and x-ray absorption at the transition metal L23 edge
M. W. Haverkort, N. Hollmann, I. P. Krug +1
A general symmetry analysis of the optical conductivity or scattering tensor is used to rewrite the conductivity tensor as a sum of fundamental spectra multiplied by simple functio…
Electronic and magnetic properties of the kagome systems YBaCo4O7 and YBaCo3MO7 (M=Al, Fe)
N. Hollmann, Z. Hu, M. Valldor +6
We present a combined experimental and theoretical x-ray absorption spectroscopy (XAS) study of the new class of cobaltates YBaCo4O7 and YBaCo3MO7 (M= Al, Fe). The focus is on the…
Crystal-field ground state of the non-centrosymmetric superconductor CePt3Si: a combined polarized soft X-ray absorption and polarized neutron study
T. Willers, B. Fak, N. Hollmann +8
We determined the crystal-field split Hund's rule ground state of the non-centrosymmetric heavy fermion superconductor CePt3Si with polarization dependent soft X-ray absorption spe…
Epitaxy, stoichiometry, and magnetic properties of Gd-doped EuO films on YSZ (001)
R. Sutarto, S. G. Altendorf, B. Coloru +12
We have succeeded in preparing high-quality Gd-doped single-crystalline EuO films. Using Eu-distillation-assisted molecular beam epitaxy and a systematic variation in the Gd and ox…
Epitaxial and layer-by-layer growth of EuO thin films on yttria-stabilized cubic zirconia (001) using MBE distillation
R. Sutarto, S. G. Altendorf, B. Coloru +11
We have succeeded in growing epitaxial and highly stoichiometric films of EuO on yttria-stabilized cubic zirconia (YSZ) (001). The use of the Eu-distillation process during the mol…
Spin blockade, orbital occupation and charge ordering in La_(1.5)Sr_(0.5)CoO4
C. F. Chang, Z. Hu, Hua Wu +9
Using Co-L_(2,3) and O-K x-ray absorption spectroscopy, we reveal that the charge ordering in La_(1.5)Sr_(0.5)CoO4 involves high spin (S=3/2) Co^2+ and low spin (S=0) Co^3+ ions. T…
Anisotropic Susceptibility of La_2-xSr_xCoO_4 related to the Spin States of Cobalt
N. Hollmann, M. W. Haverkort, M. Cwik +4
We present a study of the magnetic susceptibility of La_2-xSr_xCoO_4 single crystals in a doping range 0.3<=x<=0.8. Our data shows a pronounced magnetic anisotropy for all compound…
Insulator to semiconductor transition and magnetic properties of the one-dimensional S = 1/2 system In_2VO_5
A. Moller, T. Taetz, N. Hollmann +5
We report structural, magnetization, electrical resistivity and nuclear- and electron spin resonance data of the complex transition metal oxide In_2VO_5 in which structurally well-…
Thermodynamics of the coupled spin-dimer system TlCuCl3 close to a quantum phase transition
T. Lorenz, S. Stark, O. Heyer +4
We present thermal expansion alpha, magnetostriction and specific heat C measurements of \tal, which shows a quantum phase transition from a spin-gap phase to a Neel-ordered ground…
A New Multiferroic Material: MnWO4
O. Heyer, N. Hollmann, I. Klassen +6
We report the multiferroic behaviour of MnWO, a magnetic oxide with monoclinic crystal structure and spiral long-range magnetic order. Based upon recent theoretical predictions…