Unconventional superconductivity in electron-doped layered Li0.48(THF)yHfNCL.
We report magnetic susceptibility measurements on a layered superconductor Li0.48(THF)0.3HfNCl having Tc approximately 26 K. The present study revealed that (a) the Fermi level density of states is small, N*(EF) approximately 0.25 states/(eV spin f.u.), (b) mass enhancement is negligible, gamma; approximately 1, (c) electron-phonon coupling is weak, lambda(ep)<<1, (d) exchange enhancement is negligible, 1/(1+F(a)0) approximately 1, and (e) electronic density parameter is large, r(2D)s approximately 10.3 (i.e., low-carrier density). It is difficult to explain the origin of the high Tc in terms of the conventional phonon (BCS) mechanism of superconductivity.
Tou
H
H
Department of Physics, Tokyo Metropolitan University, Minami-osawa, Hachi-oji, Tokyo 192-0397, Japan.
Maniwa
Y
Y
Koiwasaki
T
T
Yamanaka
S
S