Magnetic-field-induced transitions and evolution of magnetotransport properties in quasi-two-dimensional KMo6O17 in the charge-density-wave phase

Abstract

Longitudinal magnetoresistivity rho(xx)(B) and Hall resistivity rho(xy)(B) of KMo6O17 single crystals have been measured up to 60 T in a pulse magnet. Remarkable and unusual features at characteristic magnetic fields were found in both rho(xx)(B) and rho(xy)(B), which were attributed to Fermi surface reconstructions caused by field-induced density-wave transitions. To understand these transitions in detail, we analyzed rho(xx)(B) and rho(xy)(B) based on a multiband model. This model successfully described the experimental results, revealing that charge carriers are increased significantly at these transitions with increasing magnetic field as a result of the Fermi surface reconstruction. In particular, the charge carriers are increased by two orders of magnitude at B-osc = similar to 40 T, above which a quantum oscillation emerges in both rho(xx)(B) and rho(xy)(B). This strongly suggests that the field-induced quantum oscillation is closely related with the induced charge carriers.