Possible Sliding Regimes in Twisted Bilayer WTe_{2}

Abstract

Inspired by the observation of increasingly one-dimensional (1D) behavior with decreasing temperature in small-angle twisted bilayers of WTe_{2} (tWTe_{2}), we theoretically explore the exotic sliding regimes that could be realized in tWTe_{2}. At zero displacement field, while hole-doped tWTe_{2} can be thought of as an array of weakly coupled conventional two-flavor 1D electron gases (1DEGs), the electron-doped regime is equivalent to coupled four-flavor 1DEGs, due to the presence of an additional "valley" degree of freedom. In the decoupled limit, the electron-doped system can thus realize phases with a range of interesting ordering tendencies, including 4k_{F} charge-density-wave and charge-4e superconductivity. Dimensional crossovers and cross-wire transport due to interwire couplings of various kinds are also discussed. We find that a sliding Luther-Emery liquid with small interwire couplings is probably most consistent with current experiments on hole-doped tWTe_{2}.