作者机构：
[Hu, XM; Peng, JS] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Hu, XM] H;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
关键词：
激光;噪声;双量子跳动
摘要：
Noise squeezing of intensity difference between the pair of sum modes may be generated in a cascade laser of A and V quantum-beats. The best achievable squeezing is up to 50% below the shot noise limit. This new kind of squeezed lasers has potential for quantum communications and precision measurements.
作者机构：
[Hu, XM; Peng, JS] Huazhong Normal Univ, Dept Phys, Whuhan 430079, Peoples R China.
通讯机构：
[Hu, XM] H;Huazhong Normal Univ, Dept Phys, Whuhan 430079, Peoples R China.
摘要：
The effect of the pump phase diffusion on the linewidth of a laser without inversion is studied. It is shown that the linewidth at equal intensity may be reduced below that for a coherent driving, enen if the net effect of the pump bandwidth leads to an increase in the linewidth. The physical mechanism is analyzed in the dressed-state picture. Furthermore, the effects of the pump phase noise on the linewidths of an inversionleess laser and a Raman laser are compared with each other.
作者机构：
[Hu, XM; Peng, JS] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Hu, XM] H;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
摘要：
In this paper we investigate the effect of two incoherent steps on the statistical properties of cascade lasers without and with inversion. It is demonstrated that the noise in the intensity difference may be reduced 50% below the shot noise. A simple physical explanation of the mechanism for squeezing is given.
作者机构：
[Huang, GM; Peng, JS; Li, GX] Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
通讯机构：
[Li, GX] H;Huazhong Normal Univ, Dept Phys, Wuhan 430079, Peoples R China.
摘要：
We have investigated the atomic coherent population trapping in a multilevel laser-induced continuum structure system including cascade two-photon processes, in which two sets of quasicontinua of excited levels to be modeled as the Bixon-Jortner quasicontinuum are laser-embedded into a previously structureless atomic continuum. The condition leading to the atomic coherent population trapping and the coherent population trapping state are given explicitly. And the effects of the Fano factors, the laser intensities and the detunings on the amount of population trapped in the atomic bound states and the populations distributed in the two sets of quasicontinua are also examined.
