Research On Cascaded-Fiber Optical Parametric Amplifier

Fiber optical parametric amplifiers (FOPA) based on four-wave mixing (FWM), which is the third order nonlinear effect. It has many advantages such as high gain, low noise coefficient and flexible working wavelength range and so on. FOPA plays an important role so it has been paid widely attention. This paper focuses on cascaded-fiber parameter amplifiers (CFOPA). The concrete contents are as follows:Firstly according to the literature material, we choose appropriate fiber parameter value to calculate the nonlinear coupling amplitude equations numerically. Then we can get the transmission evolution discipline of the pump light, signal light and idle light at any position in fibers. Through analyzing the effects between the relative phase difference of the waves and signal light, we discuss and analyze the principle that a cascade structure can improve the performance of the parametric amplification.Secondly we focus on the factors to determine signal gain, gain bandwidth and other performance parameters of two sections CFOPA, then we can see how they determine the performance of CFOPA, so we can choose appropriate parameters to make the optical amplifiers working in the best state.Thirdly we optimize the performance of CFOPA which is constituted by several HNLF and SMF sections. We use the plus wave vector of SMF to compensate the minus wave vector of HNLF. We can get the fiber length and phase mismatch we need to compensate by software numerical simulation. So we can get the universally applicable fiber parameters to improve gain or expand bandwidth in a low pump power condition.