汇报标题 (Title)：基于慢光孤子的光与原子自旋的量子压缩（Quantum Squeezing of Light and Atomic Spins Based on Slow-Light Solitons）
汇报人 (Speaker)：黄国翔 教授（华东师范大学）
汇报功夫 (Time)：2024年11月26日（周二）10:00-11:30
汇报地址 (Place)：校本部G601
约请人(Inviter)：钟建新
主办部门：量子科技钻研院/理学院物理系
汇报提要：In this talk, I shall give a presentation of our recent investigations on the quantum squeezing of slow-light solitons in coherent atomic systems working under the condition of electromagnetically induced transparency (EIT). Starting from Heisenberg-Langevin-Maxwell equations governing the quantum dynamics of atoms and probe laser field in a three-level atomic system, we derive a quantum nonlinear Schr?dinger equation controlling the evolution of the probe-field envelope. By diagonalizing effective Hamiltonian via Bogoliubov transformation, we carry out detailed calculations on the quantum fluctuations of slow-light solitons, and show that the eigenmodes of the quantum fluctuations constitute a complete and biorthonormal set, obtained by solving Bogoliubov-de Gennes equations analytically. Based on these results, we show that, due to the giant Kerr nonlinearity induced by the EIT, significant quantum squeezing of both bright and dark solitons can be realized within a very short propagation distance. We also show that it is possible to realize simultaneous quantum squeezing of light polarizations and atomic spins in a four-level atomic gas via a double EIT. The results reported here are beneficial for understanding the quantum property of slow-light solitons and for realizing quantum squeezing of light and atomic spins via EIT.
