Electronic States of Low-Dimensional Organic Conductors (DMeDCNQI) ₂Cu and α- (BEDT-TTF) ₂KHg (SCN) ₄ under Pressure

抄録

Angle-dependent magnetoresistance measurements clarified the origin of the anomalous state of the organic quasi two-dimensional conductor (BEDT-TTF) ₂KHg (SCN) ₄ to be the Peierls instability on the one-dimensional part of the Fermi surface. Pressures higher than about 0. 5 GPa were found to increase the interlayer band-width to suppress the Peierls instability. With the help of the “chemical pressure effect” precise studies of (DMeDCNQI) ₂Cu were made as functions of pressure to reveal the nature of the re-entered metallic state. Magnetoresistance and heat capacity measurements clarified the re-entered metallic state to be nothing but a normal metallic one.