| Project/Area Number |
12440098
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
固体物性Ⅱ(磁性・金属・低温)
|
|---|
| Research Institution | The University of Tokyo |
|---|
Principal Investigator |
SHIN Shik The University of Tokyo, Institute for Solid State Physics, Professor, 物性研究所, 教授 (00162785)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
YOKOYA Takayoshi The University of Tokyo, Institute for Solid State Physics, Research Associate, 物性研究所, 助手 (90311646)
|
|---|
| Project Period (FY) |
2000 – 2001
|
| Project Status |
Completed (Fiscal Year 2001)
|
| Budget Amount *help |
¥15,400,000 (Direct Cost: ¥15,400,000)
Fiscal Year 2001: ¥6,500,000 (Direct Cost: ¥6,500,000)
Fiscal Year 2000: ¥8,900,000 (Direct Cost: ¥8,900,000)
|
|---|
| Keywords | Soft x-ray laser / ultrahigh-resolutioin PES / PES with small spot size / low-Te superconductor / superconducting gap / anisotropic superconductivity / 高分解能光電子分光 / 超伝導体 / 電子状態 |
|---|
| Research Abstract |
We have constructed a low-temperature and high-resolution photoemission (PE) spectrometer for using a laser as a photon source. We have achieved an energy resolution of 0.8 meV without an energy width of light\ an angular resolution of 0.2 degree, and the lowest sample temperature of 4 K, which are the highest performance of PE spectrometer in the world.
Using this spectrometer, we have studied superconductors with a low transition temperature (low-Tc). We have observed a superconducting gap of elemental metals (Nb and Pb) as well as phonon-induced fine structures in Pb. We have concluded anisotropic s-wave superconductivity for Yni_2B_2C from an impurity-induced change in gap anisotropy. We have provided a spectroscopic evidence for a multiple gap of MgB_2. We have measured an isotropic s-wave gap and a normal-state pseudogap in Ba_<1-x>K_xBiO_3. We have observed the superconducting gap of Ba_8Si_<46> and classified it as a weak coupling superconductor. From angle-resolved study of 2H-NbSe_2, we have resolved all the Fermi surface sheets predicted by band structure calculations and have observed FS sheet dependent superconductivity.
|
