Ultrahigh birefringent nonlinear silicon-core microfiber with two zero-dispersion wavelengths

A simple silicon-core microfiber has been proposed to simultaneously achieve an ultrahigh birefringence order of 10−1, a large nonlinear coefficient, and two zero-dispersion wavelengths. The full-vector finite-element method with a circular perfectly matched layer boundary is used to simulate the properties of our proposed microfiber. It is suitable to achieve two zero-dispersion wavelengths of ∼1280 and ∼1817 nm for the x-polarized HE11 mode and of ∼1293 and ∼1695 nm for the y-polarized HE11 mode, when the major and minor diameters are, respectively, ∼1.05 and ∼0.315 μm, and the radius of the silicon core is about 135.35 nm. Meanwhile, the nonlinear coefficients of two nondegenerated HE11 modes at the wavelength of 1550 nm are ∼17.42 and ∼33.77 W−1 m−1, respectively, and the maximum birefringence is about ∼0.24 at 1550 nm wavelength. Therefore, our proposed silicon-core microfiber exhibits excellent polarization and nonlinearity performance, which enables it to be used for polarization-maintaining nonlinear signal processing, such as supercontinuum spectrum generation, parametric amplification, optical nonlinear sensor, and so on.