利用锁模飞秒脉冲激光二次谐波为抽运源,同步抽运单共振光学参量振荡器,抽运光中心波长为425nm,重复率为76MHz,脉宽180fs,光学振荡器下转换晶体采用I类共线PPKTR实验上实现了压缩度为2.58dB的正交位相压缩光.考虑到实验系统的效率,可以推知光学参量振荡器输出的下转换光压缩度为4.48dB。
We demonstrate experimentally the short pulse amplitude squeezed light from a singly resonant synchronously pumped optical parametric oscillator (SPOPO). The SPOPO operates in the frequency degenerate case and below threshold, with using a periodically poled potassium titanyl phosphate crystal. The pump laser is the second harmonic of a ultrashort mode-locked femtosecond pulse at 850 nm. The reduction of quantum noise of 2.58 dB is obtained experimentally. The squeezing extent is deduced to be 4.48 dB.