Possible quantum Hall effect in a magnetic-field-induced phase transition in the quasi-one-dimensional CDW organic conductor, HMTSF–TCNQ

• Published in: Physica. B, Condensed matter Condensed matter, 2015-03, Vol.460, p.241-244
• Main Authors: Murata, Keizo, Fukumoto, Yuhei, Yokogawa, Keiichi, Kang, Woun, Takaoka, Ryo, Tada, Ryota, Hirayama, H., Brooks, James S., Graf, David, Yoshino, Harukazu, Sasaki, Takahiko, Kato, Reizo
• Format: Article
• Language: English
• Subjects: Anomalies; Condensed matter; Conductors (devices); Low pressure; Magnetoresistance; Magnetoresistivity; Pocket; Quantum Hall effect
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2014.11.080

We have studied the angular dependence of magnetoresistance and Hall effect of the CDW organic conductor, HMTSF-TCNQ in order to see whether a magnetic-field-induced phase exists in the charge density wave (CDW) system, similarly to the magnetic-field-induced SDW phases in (TMTSF) sub(2)X. The anomaly in magnetoresistance was observed only around the pressure where the CDW is almost suppressed, i.e. around 0.8-1.1 GPa, but neither at low pressures (0 and 0.5 GPa) nor at high pressure above 2 GPa. This behavior is quite similar to that of (TMTSF) sub(2)X. At 1.1 GPa anomalies were found at fields of 0.2 T and 10 T. We speculate that at 1.1 GPa the field-induced phase is located between 0.2 T and 10 T, where 1D Fermi surface sheet and 2D Fermi-surface pocket are present. The R sub()xyshows plateau structure and R sub()xxwas very small in the same region, suggestive of quantum Hall effect.