Is a photon amplifier always polarization dependent?

Laleh Memarzadeh, Stefano Mancini

Zhizhong Yan, Haoyu He, Han Liu +6 more

Record squeezing, with squeezing parameter r ≈ 2.5 is measured in AlGaAs optical parametric amplifiers using an ultrafast pump centered at 775 nm. Polarization dependent squeezing and parametric gain were obtained with sub-photon per pulse amplifier sensitivity at 1550 nm regime.

R. W. Keys, S.J. Wilson, M. Healy +3 more

One component of polarization-dependent gain (PDG) in optical amplifiers has been shown to originate from polarization hole burning (PHB) in the erbium fibers.1 In this paper we quantify its magnitude for copumped amplifiers under operating conditions typical of those used in long-haul amplified systems. We find that PDG can be significant, even when the polarization state of the signal is circular, and that hole burning due to the polarization of the 1480-nm pump laser contributes significantly to the overall polarization-dependent gain of the fiber.

M. Iinuma

Yu.P. Peresun'ko, Valentin F. Boldyshev, E.A. Vinokurov

V.J. Mazurczyk, J.L. Zyskind

Measurement of polarization hole burning is reported for an erbium doped fiber amplifier. This effect produces a dependence of gain, measured with a weak probe, on the polarization of the saturating signal; the maximum gain occurs for probe polarizations orthogonal to the signal. The pump also contributes to the gain dependence on polarization. Reduction of the degree of polarization of both pump and signal below 10% reduces the polarization dependent gain substantially.>