Perfect continuous-variable quantum microcombs

TL;DR

This paper demonstrates the generation of a broadband, uniform, and high-quality continuous-variable quantum microcomb with 14 entangled modes and over 4 dB of squeezing, advancing scalable quantum information processing.

Contribution

The authors engineered a microresonator with an optimized mode spectrum and pump conditions to produce a broadband CV quantum microcomb with uniform squeezing across 14 modes, overcoming previous dispersion limitations.

Findings

Achieved 14 two-mode squeezed states with >4 dB squeezing.

Realized a 0.7 THz bandwidth of uniform quantum squeezing.

Demonstrated a scalable quantum resource for CV quantum technologies.

Abstract

Quantum microcombs generated in high-Q microresonators provide compact, multiplexed sources of entangled modes for continuous-variable (CV) quantum information processing. While deterministic generation of CV states via Kerr-induced two-mode squeezing has been demonstrated, achieving spectrally uniform squeezing remains challenging because of asymmetry and anomalies in the dispersion profile. Here we overcome these limitations by combining a microresonator with an engineered mode spectrum and optimized pump conditions. We realize a CV quantum microcomb comprising 14 independent two-mode squeezed states, each exhibiting more than 4 dB of raw squeezing (up to 4.3 dB) across a 0.7 THz bandwidth. This uniform, high-performance quantum resource represents a key step toward scalable, integrated CV quantum technologies operating beyond classical limits.