Forro L, Gaal R, Berger H, Fazekas P, Penc K, Kezsmarki I, Mihaly G
Department of Physics, Ecole Politechnique Federale de Lausanne, CH-1015 Lausanne, Switzerland.
Phys Rev Lett. 2000 Aug 28;85(9):1938-41. doi: 10.1103/PhysRevLett.85.1938.
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.
利用电阻率测量研究了BaVS3在压力下的相图。金属到非磁性莫特绝缘体转变的温度在压力下降低,并在量子临界点p(cr)=20 kbar时消失。我们发现了两种反常导电状态。高压金属相是一种非费米液体,由Δρ≈Tⁿ描述,其中在1<T<40 K时n = 1.2 - 1.3。在p<p(cr)时,转变之前有一个宽的前驱区,电阻率急剧增加,我们将其归因于软库仑能隙的打开。