Pressure induced quantum critical point and non-fermi-liquid behavior in BaVS3
The phase diagram of BaVS3 is studied under pressure using resistivity measurements. The temperature of the metal to nonmagnetic Mott insulator transition decreases under pressure, and vanishes at the quantum critical point p(cr) = 20 kbar. We find two kinds of anomalous conducting states. The high-pressure metallic phase is a non-Fermi liquid described by Deltarho approximately T(n) where n = 1.2-1.3 at 1<T<40 K. At p<p(cr), the transition is preceded by a wide precursor region with critically increasing resistivity which we ascribe to the opening of a soft Coulomb gap.
Forro
L
Department of Physics, Ecole Politechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland.
Gaal
R
Berger
H
Fazekas
P
Penc
K
Kezsmarki
I
Mihaly
G