Tunable quantum two-photon interference with reconfigurable metasurfaces using phase-change materials

TL;DR

This paper introduces reconfigurable metasurfaces using phase-change materials to dynamically control two-photon quantum interference at room temperature, enabling rapid, low-power quantum optical device switching.

Contribution

It presents the first adaptive metasurfaces capable of tunably controlling nonclassical two-photon interference with high speed and no static power consumption.

Findings

Tunable two-photon interference from -97.7% to 75.48%.

Switching from -59.42% to 86.09% via phase transition.

Operation at room temperature with high switching speed.

Abstract

The ability of phase-change materials to reversibly and rapidly switch between two stable phases has driven their use in a number of applications such as data storage and optical modulators. Incorporating such materials into metasurfaces enables new approaches to the control of optical fields. In this article we present the design of novel switchable metasurfaces that enable the control of the nonclassical two-photon quantum interference. These structures require no static power consumption, operate at room temperature, and have high switching speed. For the first adaptive metasurface presented in this article, tunable nonclassical two-photon interference from -97.7% (anti-coalescence) to 75.48% (coalescence) is predicted. For the second adaptive geometry, the quantum interference switches from -59.42% (anti-coalescence) to 86.09% (coalescence) upon a thermally driven crystallographic phase transition. The development of compact and rapidly controllable quantum devices is opening up promising paths to brand-new quantum applications as well as the possibility of improving free space quantum logic gates, linear-optics bell experiments, and quantum phase estimation systems.