Real-time monitoring of multimode squeezing

Kalash M, Sudharsanam A, M. Passos MH, Parigi V, Chekhova M (2026)

Publication Type: Journal article

Publication year: 2026

Journal

Nature Communications Nature Publishing Group: Nature Communications

Book Volume: 17

Article Number: 3904

Journal Issue: 1

DOI: 10.1038/s41467-026-72357-0

Abstract

Multimode squeezed light is a key resource for high-dimensional quantum technologies, enhancing metrological sensitivity, boosting communication security, and enabling parallel processing in computation. Its practical potential, however, remains constrained by the inherent single-mode operation of homodyne detection, necessitating post-processing for multimode characterization. Here, we overcome this long-standing challenge by employing multimode optical parametric amplification, enabling loss-tolerant direct detection of squeezing in each mode, which in turn permits mode sorting after amplification. As a result, we demonstrate, for the first time to the best of our knowledge, the real-time monitoring of multimode squeezing. With a spatial light modulator sorting the modes, we simultaneously measure squeezing in nine spatial modes co-propagating within one beam. Although mode sorting and filtering reduce the detection efficiency to less than 0.3%, we observe high-purity squeezing of up to − 7.9 ± 0.6 dB – to the best of our knowledge, the highest squeezing recorded for pulsed light. Furthermore, we demonstrate real-time, loss-tolerant characterization of continuous-variable entanglement and extend it to the detection of cluster states. Similar methods can be applied in the frequency domain, facilitating a crucial capability for scalable quantum technologies.

Involved external institutions

Max-Planck-Institut für die Physik des Lichts (MPL) / Max Planck Institute for the Science of Light DE Germany (DE) Sorbonne Université FR France (FR)

How to cite

APA:

Kalash, M., Sudharsanam, A., M. Passos, M.H., Parigi, V., & Chekhova, M. (2026). Real-time monitoring of multimode squeezing. Nature Communications, 17(1). https://doi.org/10.1038/s41467-026-72357-0

MLA:

Kalash, Mahmoud, et al. "Real-time monitoring of multimode squeezing." Nature Communications 17.1 (2026).

BibTeX: Download