Achieving multi-frequency state entanglement with ultra-slow multi-wave mixing

Xiaoxue Yang, Ying Wu

We propose a scheme via four-wave mixing in a double-Λ system to generate a maximally entangled state of two light beams (the probe laser beam and the four-waving mixing beam), which propagates with ultraslow group velocity. It appears to be the first scheme to achieve an ultra-slowly propagating maximally entangled state of lights.

Guangling Cheng, Wenxue Zhong, Aixi Chen

A. Bandilla, G. Drobný, Igor Jex

Zhiwei Lü, Yongkang Dong, Qiang Li

We present a method to achieve flat-top gain spectrum through overlapping multiple gain lines, which can be used to increase slow light bandwidth and relative pulse delay. A tunable gain bandwidth can be realized by changing the number of spectral lines and frequency separation between adjacent spectral lines. We demonstrate the method in a SBS-based slow light system. A phase modulator is used to modulate the phase of the pump wave, generating a pump wave with multi-line spectrum and achieving a Brillouin gain bandwidth of ~ 330 MHz.

Wenxing Shi, Fei Wang, Lihui Zhang +2 more

U. Bortolozzo, S. Residori, Jean‐Pierre Huignard

Slow-light is obtained through nonlinear wave-mixing in a liquid crystal light-valve. A deceleration of light pulses down to group velocities as small as 0.2 mm/s is achieved when two-wave-mixing is performed with a continuous pump and a time modulated signal. A model accounts for the observations in the general framework of nonlinear wave-mixing in thin media. The large group delay provided by the light-valve is exploited to enhance the spectral sensitivity of an interferometer, whereas the narrow frequency bandwidth of the two-wave-mixing gain is used to realize an adaptive holographic system that allows achieving subpicometer detection.