TITLE:
Magnetic-Field-Induced Phase Transition and a Possible Quantum Hall Effect in the Quasi-One-Dimensional CDW Organic Conductor HMTSF-TCNQ
AUTHORS:
Keizo Murata, Yuhei Fukumoto, Keiichi Yokogawa, Woun Kang, Ryo Takaoka, Ryota Tada, Hikaru Hirayama, James S. Brooks, David Graf, Harukazu Yoshino, Takahiko Sasaki, Reizo Kato
KEYWORDS:
Charge Density Wave, Magnetoresistance, Field-Induced CDW, Fermi Surface, Nesting, Quantum Hall Effect
JOURNAL NAME:
Journal of Modern Physics,
Vol.5 No.8,
May
29,
2014
ABSTRACT:
In the Temperature-Pressure
phase diagram, the quasi-one-dimensional conductor, HMTSF-TCNQ, the ground
state at ambient pressure is an insulator of charge density wave (CDW) below 30
K, while it shows a good metallic nature at higher temperature. The CDW
insulating state is suppressed by a pressure of 1 GPa, which is considered to
be a quantum critical point. Neither at 0 - 0.5 nor 2 GPa but only around this
critical point in pressure, field-induced phases appear from 0.2 T through 10
T, where Rxy is almost
constant and Rxx is very
low. These phenomena are achieved when the magnetic field is applied along the
least conducting axis. The behaviors are consistent with a kind of Quantum Hall
Effect (QHE). The field-induce phase accompanied by the QHE might be the
field-induced CDW (FICDW) similar to that of FISDW, observed in (TMTSF)2X
salts. This paper presents the latest result of the Hall effects reviewing the
history of the authors’ work on this material from preliminary to the latest
ones.