Low-Temperature Electron Spin Resonance in (TMTSF) Sub 2 PF sub 6 in the High-Pressure Metallic Phase

摘要

The electron spin resonance of (TMTSF) sub 2 PF sub 6 has been observed at low fields (H sub 0 < 110 Oe) in the high pressure, metallic phase (p greater than or equal to 6.5 kbar) in the temperature range 1 to 4 exp 0 K. The anisotropy in the g value is similar to that observed at ambient pressure above the metal-insulator transition. The linewidth is very narrow and the spin susceptibility strongly decreases as the superconducting transition is approached from above. This is interpreted as evidence for singlet-paired superconductivity. Superconductivity is observed at 1.1 exp 0 K and the critical field has angular dependence in the bc plane. These observations lead us to conclude that (TMTSF) sub 2 PF sub 6 is a singlet paired superconductor. (ERA citation 06:035668)