E. L. Ginzton Laboratory, Stanford University, 450 Via Palou, Stanford, California 94305, USA.
Opt Lett. 2010 Aug 15;35(16):2804-6. doi: 10.1364/OL.35.002804.
Ideal quantum frequency conversion (QFC) devices enable wavelength translation of a quantum state of light while preserving its essential quantum characteristics, namely photon statistics and coherence. However, the generation of noise photons due to spontaneous scattering of the strong classical pump used in the three-wave mixing process can limit QFC fidelity. We experimentally and theoretically characterize the noise properties of a difference-frequency generation device for QFC and find that fabrication errors in the quasi-phase-matching grating enhance generation of noise photons by parametric fluorescence.
理想的量子频率转换 (QFC) 设备能够在保持光的基本量子特性（即光子统计和相干性）的同时，实现量子态的波长转换。然而，由于三波混频过程中使用的强经典泵的自发散射，会产生噪声光子，从而限制 QFC 的保真度。我们实验和理论上对 QFC 的差频产生器件的噪声特性进行了表征，发现准相位匹配光栅的制造误差通过参量荧光增强了噪声光子的产生。
