Experimental investigation of supercontinuum generation in a birefringence tellurite microstructured optical fiber

Abstract

A four-hole birefringence tellurite microstructured optical fiber (BTMOF) was designed and fabricated based on 76 .5 T e O 2 − 6 Z n O − 11 . 5 L i 2 O − 6 B i 2 O 3 glass, and its core (slow and fast axes were) measured to be approximately 4.74 µm and 4.29 µm, respectively. The experimentally measured results demonstrated that the maximum supercontinuum (SC) spectra extended from ∼ 914.1 n m to ∼ 1885.1 n m when the polarization state of the pump pulse was parallel to the fast axis at 1400 nm with an average power of 460 mW. We performed numerical simulations based on the nonlinear Schrödinger equation, which support the experimentally measured results. The SC generation in birefringent silica microstructured fiber with the same geometric parameters was simulated, and the results showed that the enhanced nonlinear refractive index of the BTMOF yielded a spectrum with a significantly larger bandwidth. Furthermore, the two polarization states along the fast axis and slow axis exhibit different dispersion characteristics, which provide a convenient way of tuning the properties of the generated SC. This work highlights BTMOF as a promising platform for the development of a SC light source, which can be widely used in food quality inspection, early cancer diagnostics, gas sensing, and high-spatial-resolution imaging.