Anomalous Quantum Metal Phase in TiSe2

Abstract

The superconductor-insulator transition in low dimensional (\(D {\,\le \,}2\)) electronic systems has been extensively studied since the late 1980s. In the early stages of this research area, it was found experimentally that, by either tuning the thickness of a Bi film deposited Ge [2] or changing the external magnetic field in InOx [3], the system can actually undergo a superconductor insulator transition, apparently without an intermediate metallic phase (see Fig. 5.1). At zero temperature (\(T \rightarrow 0\)), systems with large thickness (small magnetic field) show zero resistance, which indicates a superconducting ground state, while for small thickness (high magnetic field), an insulator with infinite resistance is achieved.