Directional field-induced metallization of quasi-one-dimensional Li0.9Mo6O17.

ABSTRACT

We report a detailed magnetotransport study of the highly anisotropic quasi-one-dimensional oxide Li(0.9)Mo(6)O(17) whose in-chain electrical resistivity diverges below a temperature T_{min} approximately 25 K. For T < T_{min}, a magnetic field applied parallel to the conducting chain induces a large negative magnetoresistance and, ultimately, the recovery of a metallic state. We show evidence that this insulator-metal crossover is a consequence of field-induced suppression of a density-wave gap in a highly one-dimensional conductor. At the highest fields studied, there is evidence for the possible emergence of a novel superconducting state with an onset temperature T_{c} > 10 K.