Electrostatic control of valley-dependent phase in tilted Dirac/Weyl channels

Abstract

Valley degrees of freedom represent a promising resource for solid-state quantum information. This work demonstrates electrostatic control of the valley-dependent phase in tilted Dirac/Weyl semimetals. When wave packets traverse a shaped electrostatic barrier, the valley-dependent tilt induces differential spatial drift and dwell times, resulting in the accumulation of a continuously tunable relative dynamical phase. The barrier thereby functions as a valley-phase shift element. Time-dependent transport simulations employing a coupled two-valley model yield electrically tunable relative phases between equal-energy valleys, including $\ddot{I}€/4$, $\ddot{I}€/2$, and $\ddot{I}€$, with high transmission probabilities.