Error mitigation on a near-term quantum photonic device

TL;DR

This paper introduces two low-overhead schemes to mitigate photon loss in Gaussian Boson Sampling devices, enhancing their performance without extensive hardware modifications, thus enabling more practical near-term photonic quantum applications.

Contribution

The paper proposes novel loss mitigation techniques relying on measurement data collection and classical post-processing, avoiding costly error correction codes.

Findings

Photon loss effects can be significantly suppressed with moderate classical post-processing.

The schemes require minimal hardware modifications or none at all.

Loss mitigation improves the accuracy of sampling probability estimation.

Abstract

Photon loss is destructive to the performance of quantum photonic devices and therefore suppressing the effects of photon loss is paramount to photonic quantum technologies. We present two schemes to mitigate the effects of photon loss for a Gaussian Boson Sampling device, in particular, to improve the estimation of the sampling probabilities. Instead of using error correction codes which are expensive in terms of their hardware resource overhead, our schemes require only a small amount of hardware modifications or even no modification. Our loss-suppression techniques rely either on collecting additional measurement data or on classical post-processing once the measurement data is obtained. We show that with a moderate cost of classical post processing, the effects of photon loss can be significantly suppressed for a certain amount of loss. The proposed schemes are thus a key enabler for applications of near-term photonic quantum devices.