Continuous variable entanglement from two spatially separated squeezed states

Ray-Kuang Lee^1,2,3, Chien-Ming Wu¹, Ole Steuernage¹, Hsien-Yi Hsieh¹, Huali Chen^2*

¹Institute of Photonics Technologies, National Tsing Hua University, Hsinchu, Taiwan
²Department of Physics, National Tsing Hua University, Hsinchu, Taiwan
³Department of Electrical Engineering, National Tsing Hua University, Hsinchu, Taiwan

* Presenter:Huali Chen, email:Chl20171@outlook.com

Coupled through a beam spitter, we experimentally generate two squeezed vacuum states from two optical parameter oscillators, with 8dB and 6dB measured separately, to prepare continuous variable entanglement. The corresponding two-mode squeezed states, both the density matrix and Wigner functions, are reconstructed with the help of the maximum likelihood method. Moreover, even with the noisy environment, the inseparability (non-locality) is verified by joint measurements with two sets balance homodyne detectors.

Keywords: Squeezed vacuum state, Entanglement, Balanced Homodyne Detector