Arbitrarily High Super-Resolving Phase Measurements at Telecommunication Wavelengths

TL;DR

This paper demonstrates two experiments achieving phase super-resolution at telecommunication wavelengths without entanglement, using standard lasers and detectors, with one experiment reaching a 30-fold resolution increase.

Contribution

The work introduces methods for high-resolution phase measurements at telecom wavelengths without entanglement or joint detection, including a simple, high-resolution approach in the time domain.

Findings

Achieved 30-fold phase super-resolution.

Demonstrated super-resolution without entanglement.

Implemented in both space and time domains.

Abstract

We present two experiments that achieve phase super-resolution at telecommunication wavelengths. One of the experiments is realized in the space domain and the other in the time domain. Both experiments show high visibilities and are performed with standard lasers and single-photon detectors. The first experiment uses six-photon coincidences, whereas the latter needs no coincidence measurements, is easy to perform, and achieves, in principle, arbitrarily high phase super-resolution. Here, we demonstrate a 30-fold increase of the resolution. We stress that neither entanglement nor joint detection is needed in these experiments, demonstrating that neither is necessary to achieve phase super-resolution.