EPJ Quantum Technol. (2020) 7: 10
https://doi.org/10.1140/epjqt/s40507-020-00085-5

Research

Enhanced Hanbury Brown and Twiss interferometry using parametric amplification

¹ College of Mathematical and Physical Sciences, Qingdao University of Science and Technology, Qingdao, China
² Hearne Institute for Theoretical Physics and Department of Physics & Astronomy, Louisiana State University, Baton Rouge, USA
³ Quantum Photonics Laboratory, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, USA
⁴ Department of Physics, Ocean University of China, Qingdao, China
⁵ NYU-ECNU Institute of Physics, NYU Shanghai, Shanghai, China
⁶ CAS-Alibaba Quantum Computing Laboratory, CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai, China

^* e-mail: cyou2@lsu.edu

Received: 5 February 2020
Accepted: 15 June 2020
Published online: 29 June 2020

Abstract

The Hanbury Brown and Twiss (HBT) interferometer was proposed to observe intensity correlations of starlight to measure a star’s angular diameter. As the intensity of light that reaches the detector from a star is very weak, one cannot usually get a workable signal-to-noise ratio. We propose an improved HBT interferometric scheme incorporating optical parametric amplifiers (OPA) into the system to amplify the correlation signal. Remarkably, for weak star light, the signal-to-noise ratio (SNR) in the new HBT interferometric scheme is much better than that of conventional HBT interferometer. Our work is valuable in measuring a star whose intensity at the detector is low and maybe also applicable in remote sensing and long-distance quantum imaging where the light passed through the object is weak after a long distance transmission.