A squeezed quantum microcomb on a chip

Zijiao Yang; Mandana Jahanbozorgi; Dongin Jeong; Shuman Sun; Olivier Pfister; Hansuek Lee; Xu Yi

doi:10.1038/s41467-021-25054-z

A squeezed quantum microcomb on a chip

Nat Commun. 2021 Aug 6;12(1):4781. doi: 10.1038/s41467-021-25054-z.

Authors

Zijiao Yang^#^{1

2}, Mandana Jahanbozorgi^#¹, Dongin Jeong³, Shuman Sun¹, Olivier Pfister², Hansuek Lee^{3

4}, Xu Yi^{5

6}

Affiliations

¹ Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA.
² Department of Physics, University of Virginia, Charlottesville, VA, USA.
³ Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea.
⁴ Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, South Korea.
⁵ Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, VA, USA. yi@virginia.edu.
⁶ Department of Physics, University of Virginia, Charlottesville, VA, USA. yi@virginia.edu.

^# Contributed equally.

Abstract

The optical microresonator-based frequency comb (microcomb) provides a versatile platform for nonlinear physics studies and has wide applications ranging from metrology to spectroscopy. The deterministic quantum regime is an unexplored aspect of microcombs, in which unconditional entanglements among hundreds of equidistant frequency modes can serve as critical ingredients to scalable universal quantum computing and quantum networking. Here, we demonstrate a deterministic quantum microcomb in a silica microresonator on a silicon chip. 40 continuous-variable quantum modes, in the form of 20 simultaneously two-mode squeezed comb pairs, are observed within 1 THz optical span at telecommunication wavelengths. A maximum raw squeezing of 1.6 dB is attained. A high-resolution spectroscopy measurement is developed to characterize the frequency equidistance of quantum microcombs. Our demonstration offers the possibility to leverage deterministically generated, frequency multiplexed quantum states and integrated photonics to open up new avenues in fields of spectroscopy, quantum metrology, and scalable, continuous-variable-based quantum information processing.