Engineering quantum interference in van der Waals heterostructures

TL;DR

This paper introduces a method to achieve tunable valley coherence in 2D heterostructures, enabling active valleytronic quantum devices through electrostatic control of anisotropic polaritonic modes.

Contribution

It demonstrates for the first time electrostatic tunability of valley coherence in heterostructures using anisotropic plasmons and hyperbolic phonon polaritons.

Findings

Achieved up to 80% valley coherence at room temperature.

Demonstrated electrostatic tunability of valley coherence.

Proposed two practical implementations using phosphorene and MoO3.

Abstract

In this paper, we present a novel route to tunable spontaneous valley coherence in heterostructures of two dimensional valleytronic materials with other layered materials hosting anisotropic polaritonic modes. We first discuss the dependence of this coherence on the conductivity tensor of the anisotropic part of a general heterostructure and on its geometrical configuration. Subsequently, we propose two implementations - one, using anisotropic plasmons in phosphorene and another with hyperbolic phonon polaritons in MoO3. In both these systems we show for the first time electrostatic tunability of the spontaneous valley coherence achieving unprecedented values of up to 80% in the near to mid infrared wavelengths at room temperature. The tunability of this valley coherence shown in these heterostructures will enable the realization of active valleytronic quantum circuitry.