Quantum CZ Gate based on Single Gradient Metasurface

TL;DR

This paper introduces a novel quantum CZ gate implementation using a single gradient metasurface, enabling integrated, polarization- and path-encoded quantum logic operations with potential for scalable quantum device integration.

Contribution

It presents a new metasurface-based scheme for realizing quantum CZ gates that supports multiple configurations and enhances integration of quantum logical functions.

Findings

Supports multiple CZ gate configurations on one metasurface

Enables polarization- and path-encoded quantum gates

Improves integration level of quantum devices

Abstract

We propose a scheme to realize quantum controlled-Z (CZ) gates through single gradient metasurface. Using its unique parallel beam-splitting feature, i.e., a series of connected beam splitters with the same splitting ratio, one metasurface can support a CZ gate, several independent CZ gates, or a cascaded CZ gates. Taking advantage of the input polarization determined output path-locking feature, both polarization-encoded and path-encoded CZ gates can be demonstrated on the same metasurface, which further improves the integration level of quantum devices. Our research paves the way for integrating quantum logical function through the metasurface.