Measurement-device-independent entanglement detection for continuous-variable systems

Abstract

We study the detection of continuous-variable entanglement, for which most of the existing methods designed so far require a full specification of the devices, and we present protocols for entanglement detection in a scenario where the measurement devices are completely uncharacterised. We first generalise, to the continuous variable regime, the seminal results by Buscemi [PRL 108, 200401(2012)] and Branciard et al. [PRL 110, 060405 (2013)], showing that all entangled states can bedetected in this scenario. Most importantly, we then describe a practical protocol that allows for the measurement-device-independent certification of entanglement of all two-mode entangled Gaussian states. This protocol is feasible with current technology as it makes only use of standard optical setups such as coherent states and homodyne measurements.