Quantum enhanced joint measurement of two conjugate observables with an SU(1, 1) interferometer
Yuhong Liu, Jiamin Li, Nan Huo, Xiaoying Li, Z. Y. Ou · 2017
We jointly measure the phase and amplitude modulation of an optical field with the newly developed SU(1,1) interferometer. We simultaneously achieve a signal-to-noise ratio improvement of 1.1 and 1 dB over the standard quantum limit in amplitude and phase measurement.