Zeno Blockade Enabling Photonic Quantum Optimization

TL;DR

This paper proposes an optical quantum optimizer using non-linear optics and Zeno effects to enforce constraints, aiming to solve maximum independent set problems with potential advantages over existing methods.

Contribution

It introduces a novel approach combining Zeno effects and linear protocols for quantum optimization, expanding the implementation possibilities in photonic systems.

Findings

Coherent Zeno effect implementation outperforms incoherent versions.

Numerical studies show potential for error mitigation and improved performance.

The approach can be viewed as entropy computing or quantum annealing within a constrained subspace.

Abstract

In this work we explore the potential of implementing an optical quantum optimizer using non-linear optics, specifically using sum-frequency generation and/or two photon absorption. This proposal uses Zeno effects to enforce independence constraints and then a linear protocol to find a maximum independent set in a way where the elements of the set can be weighted. Our proposal can either be viewed as an implementation of the entropy computing paradigm presented in [Nguyen et.~al.~Communications Physics 1, 411, 8] which uses real rather than imaginary time evolution, or as quantum annealing within a Zeno constrained subspace. We discuss how such a device could be built, and considerations such as error mitigation, particularly for photon-loss errors. We numerically study aspects of the protocol, including the effect of coherent versus incoherent incarnations of the Zeno effect, finding superior performance from the former.