Spasibko K Yu, Iskhakov T Sh, Chekhova M V
Department of Physics, M. V. Lomonosov Moscow State University, Leninskie Gory, 119992 Moscow, Russia.
Opt Express. 2012 Mar 26;20(7):7507-15. doi: 10.1364/OE.20.007507.
High-gain parametric down-conversion (PDC) is a source of bright squeezed vacuum, which is a macroscopic nonclassical state of light and a promising candidate for quantum information applications. Here we study its properties, such as the intensity spectral width and the spectral width of pairwise correlations. In agreement with the theory, we observe an increase in the spectral width by 27% compared with the low-gain PDC. Frequency cross- and auto-correlations are registered by measuring the reduction of noise in the difference of PDC intensities at various pairs of wavelengths. The noise reduction plots also demonstrate super-bunching typical for collinear frequency-degenerate PDC.
高增益参量下转换（PDC）是明亮压缩真空的一个来源，明亮压缩真空是光的一种宏观非经典态，也是量子信息应用的一个有前景的候选者。在这里，我们研究它的特性，比如强度光谱宽度和成对关联的光谱宽度。与理论一致，我们观察到与低增益PDC相比，光谱宽度增加了27%。通过测量不同波长对处PDC强度差的噪声降低来记录频率交叉关联和自关联。噪声降低图还展示了共线频率简并PDC典型的超聚束现象。
