Multi-parameter Sensing Based on the Stimulated Brillouin Scattering in Ring Core Fibers.

In this paper, we designed two ring core fibers (RCFs) for the simultaneous sensing of temperature and strain using stimulated Brillouin scattering. The designed fibers are referred to as step index RCF (SI-RCF) and graded index RCF (GI-RCF). Numerical simulations proved that the designed RCFs achieve temperature sensitivities of 1.928 MHz/°C for SI-RCF and 1.872 MHz/°C for GI-RCF, and strain sensitivities of 0.087 MHz/με for SI-RCF and 0.0842 MHz/με for GI-RCF. The respective optimal errors for the simultaneous sensing of temperature and strain have been evaluated and discussed for both designed RCFs. The reported results and the performed comparisons with literature confirm that the designed RCFs sensors could find applications in next generation Brillouin sensing systems for enabling temperature and strain discrimination.