Fermi surface of Sr2RuO4 observed by soft x-ray angle-resolved photoemission spectroscopy
Inquiry number
SOL-0000000948
Beamline
BL25SU (Soft X-ray Spectroscopy of Solid)
Scientific keywords
| A. Sample category | inorganic material |
|---|---|
| B. Sample category (detail) | superconductor, solid-state crystal, crystal |
| C. Technique | photoemission, photoionization |
| D. Technique (detail) | photoelectron spectra |
| E. Particular condition | ultra-high vacuum, low-T (~ liquid He) |
| F. Photon energy | soft X-ray |
| G. Target information | electronic state |
Industrial keywords
| level 1---Application area | Semiconductor, storage device, industrial material |
|---|---|
| level 2---Target | silicon semiconductor, compound semiconductor, HD,MO |
| level 3---Target (detail) | magnetic layer |
| level 4---Obtainable information | electronic state |
| level 5---Technique | XPS |
Classification
M40.40 soft x-ray spectroscopy, M50.10 photoelectron spectroscopy
Body text
Soft x-ray angle-resolved photoemission spectroscopy (SX-ARPES) is a powerful tool to investigate electronic states of solids. Band dispersions or Fermi surfaces can be observed by ARPES. SX-ARPES is rather sensitive to bulk of solids in comparison with ARPES in the ultraviolet region because escape depths of photoelectrons are increased with increasing the excitation energy. The figure shows mapping of Fermi surfaces of the superconducting Sr2RuO4 and nonsuperconducting Sr1.8Ca0.2RuO4 measured at BL25SU. One hole-like (α) and two electron-like (β, γ) Fermi surfaces are clearly observed in Sr2RuO4. This result is consistent with the suggestion from quantum oscillation measurements and band structure calculations. The electronic structures are found to be qualitatively unchanged between Sr2RuO4 and Sr1.8Ca0.2RuO4. This supports the hypothesis that the Ca ions behaving as impurities and/or defects increased by the Ca substitution break the superconductivity.
[ A. Sekiyama, S. Kasai, M. Tsunekawa, Y. Ishida, M. Sing, A. Irizawa, A. Yamasaki, S. Imada, T. Muro, Y. Saitoh, Y. Onuki, T. Kimura, Y. Tokura and S. Suga, Physical Review B 70, 060506 (2004), Fig. 3,
©2004 American Physical Society ]
Source of the figure
Original paper/Journal article
Journal title
Phys. Rev. B 70, 060506 (2004)
Figure No.
3
Technique
SX-ARPES provides information of k-dependent electronic states of solids. Energy analysis and angle resolving of photoelectrons is performed by a hemispherical electron analyzer (SES200). Measurements are carried out in a UHV condition. Samples should have electric conductivity to avoid charging. Clean surfaces of the samples are obtained by cleaving or fracture in the UHV chamber.
Source of the figure
No figure
Required time for experimental setup
2 hour(s)
Instruments
| Instrument | Purpose | Performance |
|---|---|---|
| Photoemission Spectrometer (PES) | Angle-resolved photoemission spectroscopy | angular resolution |
References
| Document name |
|---|
| Pys. Rev. B 70, 060506 (2004) |
Related experimental techniques
Questionnaire
The measurement was possible only in SPring-8. Impossible or very difficult in other facilities.
This solution is an application of a main instrument of the beamline.
Ease of measurement
Middle
Ease of analysis
With a great skill
How many shifts were needed for taking whole data in the figure?
More than ten shifts