Witnessing entanglement in phase space using inefficient detectors

TL;DR

This paper introduces a method to detect entanglement in phase space using highly inefficient detectors without needing error correction or prior efficiency knowledge, enabling entanglement witnessing with as low as 40% efficiency.

Contribution

It presents a novel scheme for witnessing entanglement that is robust to detector inefficiency and does not require additional error correction or prior efficiency calibration.

Findings

Entanglement can be witnessed with detection efficiency as low as 40%.

The scheme works for single photon entangled and two-mode squeezed states.

No additional error correction process is needed.

Abstract

We propose a scheme for witnessing entanglement in phase space by significantly inefficient detectors. The implementation of this scheme does not require any additional process for correcting errors in contrast to previous proposals. Moreover, it allows us to detect entanglement without full a priori knowledge of the detection efficiency. It is shown that entanglement in single photon entangled and two-mode squeezed states can be witnessed with detection efficiency as low as 40%. Our approach enhances the possibility of witnessing entanglement in various physical systems using current detection technologies.