Four-wave mixing in fibers for bright squeezed vacuum

点击翻译按钮获取中文摘要

Four-wave mixing in fibers for bright squeezed vacuumThe aim of the project is to produce entangled states of light by four-wave mixing (FWM) with many photons (>100). The quantum states of light find applications in SU(1,1) interferometry, which yields a quantum enhanced sensitivity.In the planned experiment, a strong pump light is propagated along a suitable photonic-crystal fiber. The FWM will lead to the spontaneous conversion of two pump photons to two other photons, the signal and idler beams, defined by their frequency. If the process has very high gain and is not entirely spontaneous, but seeded by injecting a signal, high photon numbers can be achieved at the fiber output, maintaining the strong quantum correlations between signal and idler. The quantum state of light is referred to as 'bright squeezed vacuum' [1]. If this light source is used in interferometry, the Heisenberg limit of interferometers, which is a nonclassical limit, can be reached.Thus in a second stage of the project, this light will be used in interferometry, in which the reverse FWM interaction creates nonlinear interference between the produced signal and idler beams. The increase in sensitivity compared to a linear classical interferometer scales as the square root of the photon number in the interferometer, beating the classical noise limits of interferometers. The project involves pulsed as well as continuous lasers, fiber optics, spectrometry, and single photon counting.The project will be carried out in collaboration and intellectual exchange with Prof. Chekhova at the Max Planck Institute of Light, Germany.[1] I.N. Agafonov, M.V. Chekhova, and G. Leuchs, Two-Color Bright Squeezed Vacuum. Phys. Rev. A 82, 011801(R) (2010).