Low-Noise Integrated Phase-Sensitive Waveguide Parametric Amplifiers

Abstract

Low-noise optical amplifiers play a vital role in optical communications and signal processing. Recently, there has been a pursuit for compact, waveguide-based, parametric amplifiers which employ the four-wave mixing process relying on the 3 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rd</sup> order nonlinearity, χ <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">(3)</sup> , of the material. Here, we present an analytic model for the gain and noise figure of phase-sensitive parametric amplifiers based on nonlinear optical waveguides, which includes the impact of the linear loss of the waveguide. We provide insights into the importance of this loss for the gain, but more importantly also for the amplifier noise figure. In particular, we study waveguides based on Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> and find that a gain of 28 dB with a 0.8 dB noise figure is feasible in a 3 m long waveguide having a loss of 1.5 dB/m. We finally investigate the impact of the Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> waveguide cross section on the dispersion and the nonlinear coefficient for the improvement of PSA performance.