Measurement of the wavefunction for a biphoton state with homodyne detection using least squares estimation
Yashuai Han, Daohua Wu, Katsuyuki Kasai, Lirong Wang, Masayoshi Watanabe, Yun Zhang · Journal of Optics · 2019
Abstract We report the measurement of wave function for a biphoton state with continuous variables (CV) by homodyne detection. The biphoton interference occurs on an optical parametric oscillator, which is seeded with a coherent state. A set of second-order correlation function values for the output field are recorded when the intensity coherent state is varied. The wave function, which includes both magnitude and argument for a complex parameter of the biphoton state, is reconstructed using the least square estimation method. This may introduce another approach to characterizing a biphoton state in the regime of CV.