Displacement of propagating squeezed microwave states

TL;DR

This paper demonstrates the successful displacement of propagating squeezed microwave states without degrading squeezing or entanglement, advancing quantum communication techniques with continuous variables.

Contribution

The authors experimentally implement displacement of propagating squeezed microwave states and show that squeezing and entanglement are preserved across various displacement amplitudes.

Findings

No degradation of squeezing at strong displacements

Path entanglement remains constant over wide displacement range

Displacement operation is effective for quantum communication protocols

Abstract

Displacement of propagating quantum states of light is a fundamental operation for quantum communication. It enables fundamental studies on macroscopic quantum coherence and plays an important role in quantum teleportation protocols with continuous variables. In our experiments we have successfully implemented this operation for propagating squeezed microwave states. We demonstrate that, even for strong displacement amplitudes, there is no degradation of the squeezing level in the reconstructed quantum states. Furthermore, we confirm that path entanglement generated by using displaced squeezed states stays constant over a wide range of the displacement power.