Temperature Dependence of the Spontaneous Brillouin Scattering Spectrum in Microstructure Fiber with Small Core

The almost equal height dual peak spontaneous Brillouin scattering spectrum of a piece of microstructure fiber with a small core was investigated at various temperatures using the heterodyne method. The central frequencies of the two peaks increase linearly with increasing temperature with temperature coefficients of 1.05 MHz/°C and 1.13 MHz/°C. The height difference between the two peaks decreases linearly with a coefficient of −0.06 dB/°C. The results show that microstructure fibers with a small core have great potential for fiber Brillouin distributed sensing.