Programmable and sequential Gaussian gates in a loop-based single-mode photonic quantum processor

TL;DR

This paper introduces a novel loop-based single-mode photonic quantum processor capable of performing universal, scalable, and programmable quantum operations, demonstrated through Gaussian and squeezing gates, advancing photonic quantum computing.

Contribution

The paper presents a new loop-based photonic quantum processor that is universal, scalable, and programmable, enabling arbitrary quantum operations on a single optical mode.

Findings

Successfully demonstrated programmable Gaussian gates

Implemented multi-step squeezing gates

Proved potential for universal quantum operations

Abstract

A quantum processor to import, process, and export optical quantum states is a common core technology enabling various photonic quantum information processing. However, there has been no photonic processor which is simultaneously universal, scalable, and programmable. Here, we report on an original loop-based single-mode versatile photonic quantum processor which is designed to be universal, scalable, and programmable. Our processor can perform arbitrarily many steps of programmable quantum operations on a given single-mode optical quantum state by time-domain processing in a dynamically controlled loop-based optical circuit. We use this processor to demonstrate programmable single-mode Gaussian gates and multi-step squeezing gates. In addition, we prove that the processor can perform universal quantum operations by injecting appropriate ancillary states and also be straightforwardly extended to a multi-mode processor. These results show that our processor is programmable, scalable, and potentially universal, leading to be suitable for general-purpose applications.