Temperature-Dependent Change of Correlated Electronic States in Yb4As3and Yb4(As1-xSbx)3Probed by High Resolution Photoemission Spectroscopy

In order to study the electronic states of solids, using high-resolution, low-temperature photoemission spectroscopy (PES) with tunable photon energies, we have constructed a high-resolution undulator beamline operating in the photon-energy range 26–300 eV at the compact 700 MeV electron-storage ring HiSOR located at Hiroshima University. By way of gas-phase experiments, with photon flux larger than 2 × 1010 photons/s, photon-energy resolving powers of E/ΔE > 16000 and 3800 were obtained at hν ~ 48 eV and ~ 244 eV, respectively. High-resolution PES experiments on evaporated Au at 8 K were performed at the beamline with a total energy resolution of ΔE = 12 meV at hν = 48 eV. Among the first experiments from the beamline, a resonant photoemission study of UNiSn is presented. The U 5f derived peak is significantly enhanced at hν = 98 eV.

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High-resolution temperature-dependent photoemission spectroscopy of FeSi: Evidence for localized states

Physical Review B ◽

10.1103/physrevb.50.8915 ◽

1994 ◽

Vol 50 (12) ◽

pp. 8915-8917 ◽

Cited By ~ 26

Author(s):

A. Chainani ◽

T. Yokoya ◽

T. Morimoto ◽

T. Takahashi ◽

S. Yoshii ◽

...

Keyword(s):

High Resolution ◽

Localized States ◽

Photoemission Spectroscopy ◽

Temperature Dependent

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TEMPERATURE-DEPENDENT HIGH-RESOLUTION PHOTOEMISSION SPECTROSCOPY OF YbXCu4 (X=In, Cd, Mg)

Surface Review and Letters ◽

10.1142/s0218625x02003378 ◽

2002 ◽

Vol 09 (02) ◽

pp. 1079-1083 ◽

Cited By ~ 2

Author(s):

H. SATO ◽

Y. NISHIKAWA ◽

F. NAGASAKI ◽

H. FUJINO ◽

Y. TAKEDA ◽

...

Keyword(s):

High Resolution ◽

Valence Band ◽

Energy Resolution ◽

High Energy ◽

The Other ◽

High Energy Resolution ◽

Photoemission Spectroscopy ◽

Temperature Dependent ◽

Other Hand ◽

Increasing Temperature

Valence-band and Yb 4d photoemission spectra of YbXCu 4 (X=In, Cd, Mg) have been measured with high energy resolution from 10 to 300 K. In the valence-band photoemission spectra of YbInCu 4 and YbCdCu 4, the structure due to the Yb 2+ 4f 7/2 states is clearly observed near the Fermi level (E F ) at 10 K. The intensity of the Yb 2+ 4f 7/2 structure decreases with increasing temperature and the structure almost disappears at 300 K. The amount of the enhancement from 50 to 107 K is much stronger for YbInCu 4 than for YbCdCu 4. On the other hand, the Yb 2+ 4f 7/2 structure of YbMgCu 4 is observed as a broad peak near E F and the spectra show little temperature dependence. In the Yb 4d photoemission spectra of YbInCu 4 and YbCdCu 4, the structures due to the Yb 2+ and Yb 3+ states are recognized. The intensity ratio Yb 2+/ Yb 3+ increases with decreasing temperature. In the Yb 4d spectra of YbMgCu 4, on the other hand, almost only structures due to Yb 2+ states are observed.

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Effects of temperature dependent chemical potential on the Seebeck coefficient of TiS2 thermoelectric material

MRS Proceedings ◽

10.1557/opl.2011.513 ◽

2011 ◽

Vol 1314 ◽

Cited By ~ 1

Author(s):

Tsunehiro Takeuchi ◽

Akio Yamamoto ◽

Koto Ogawa

Keyword(s):

High Resolution ◽

Seebeck Coefficient ◽

Temperature Dependence ◽

Thermoelectric Material ◽

Chemical Potential ◽

Photoemission Spectroscopy ◽

Temperature Dependent ◽

Angle Resolved Photoemission Spectroscopy ◽

Guiding Principle ◽

Effects Of Temperature

ABSTRACTThe relation between chemical potential and Seebeck coefficient was investigated by using high-resolution angle resolved photoemission spectroscopy. The temperature dependence of chemical potential was experimentally determined for the n-type TiS2 thermoelectric material and compared with the measured Seebeck coefficient. We found that the temperature dependence of chemical potential of TiS2 is significantly large, and its effect on Seebeck coefficient is not negligible. This fact strongly indicates that the temperature dependence of chemical potential has to be properly understood to construct the guiding principle for developing new, practical thermoelectric materials.

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Ce4f STATES IN CePd2Si2 AND CeNi2Si2 INVESTIGATED BY RESONANT PHOTOEMISSION SPECTROSCOPY

Surface Review and Letters ◽

10.1142/s0218625x02003305 ◽

2002 ◽

Vol 09 (02) ◽

pp. 1035-1039 ◽

Cited By ~ 1

Author(s):

K. MIMURA ◽

Y. OKABAYASHI ◽

H. MIZOHATA ◽

D. SAKIYAMA ◽

O. SAKAI ◽

...

Keyword(s):

High Resolution ◽

Relative Intensity ◽

Electronic States ◽

Kondo Temperature ◽

Photoemission Spectroscopy ◽

Present Calculation ◽

Intermediate Valence ◽

Final State ◽

Resonant Photoemission ◽

Kondo Resonance

Ce 4f electronic states in an antiferromagnetic Kondo compound CePd 2 Si 2 and a strong intermediate-valence compound CeNi 2 Si 2 have been investigated by means of high-resolution Ce 4d–4f resonant photoemission spectroscopy at 12 K. The relative intensity of the f5/21 to f7/21 final state in the Ce 4f spectrum for CeNi 2 Si 2 is stronger than the relative intensity for CePd 2 Si 2, indicating that the intensity of Kondo resonance scales the Kondo temperature since the Ce 4f spectrum near the Fermi level dominantly reflects the bulk component. Both Ce 4f spectra have been well fitted by the spectral calculations based on a single impurity Anderson model with consideration of the bulk and surface components. Our present calculation indicates that the model is applicable to the analyses of the Ce 4f spectra of the weakly and strongly hybridized systems.

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Rotatable high-resolution ARPES system for tunable linear-polarization geometry

Journal of Synchrotron Radiation ◽

10.1107/s1600577517008037 ◽

2017 ◽

Vol 24 (4) ◽

pp. 836-841 ◽

Cited By ~ 21

Author(s):

H. Iwasawa ◽

K. Shimada ◽

E. F. Schwier ◽

M. Zheng ◽

Y. Kojima ◽

...

Keyword(s):

High Resolution ◽

Linear Polarization ◽

Electronic States ◽

Field Vector ◽

Photoemission Spectroscopy ◽

Angle Resolved Photoemission Spectroscopy ◽

Detection Plane ◽

Linearly Polarized ◽

Dipole Selection Rule ◽

Synchrotron Radiation Center

A rotatable high-resolution angle-resolved photoemission spectroscopy (ARPES) system has been developed to utilize tunable linear-polarization geometries on the linear undulator beamline (BL-1) at Hiroshima Synchrotron Radiation Center. By rotating the whole ARPES measurement system, the photoelectron detection plane can be continuously changed from parallel to normal against the electric field vector of linearly polarized undulator radiation. This polarization tunability enables us to identify the symmetry of the initial electronic states with respect to the mirror planes, and to selectively observe the electronic states based on the dipole selection rule in the photoemission process. Specifications of the rotatable high-resolution ARPES system are described, as well as its capabilities with some representative experimental results.

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DIRECT EVIDENCE FOR ITINERANT MAGNETITE ABOVE AND BELOW THE VERWEY TRANSITION TEMPERATURE

Surface Review and Letters ◽

10.1142/s0218625x02003147 ◽

2002 ◽

Vol 09 (02) ◽

pp. 907-912 ◽

Cited By ~ 4

Author(s):

Y. Q. CAI ◽

K. NAKATSUJI ◽

S. OHNO ◽

T. IIMORI ◽

M. YAMADA ◽

...

Keyword(s):

Transition Temperature ◽

Synchrotron Radiation ◽

Direct Evidence ◽

Electronic States ◽

Photoemission Spectroscopy ◽

Partial Density ◽

Verwey Transition ◽

Temperature Dependent ◽

Angle Resolved Photoemission Spectroscopy ◽

Minority Spin

The valence electronic states of Fe 3 O 4(111) films on Pt(111) were studied using temperature-dependent spin- and angle-resolved photoemission spectroscopy with synchrotron radiation. The majority- and minority-spin partial density of states (DOS) has been obtained at 300 K and 100 K, above and below the Verwey transition temperature (TV ~ 120 K ). The spectra still show substantial k-dependence at 100 K in the 3d region. This provides the most direct experimental evidence that the 3d electrons are itinerant even at T < TV.

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