Wavelength stabilization of a semiconductor laser using wavelength-dependent frequency shift by stimulated Brillouin scattering

Abstract

© The Authors. We propose a method of stabilizing the center wavelength of a semiconductor laser using the wavelength- dependent frequency shift of Stokes wave induced by stimulated Brillouin scattering in fiber. Due to the nonlinear behavior of fiber to a strong input power, Stokes wave is generated and its frequency varies in inversely proportional to the input wavelength over a small wavelength range of < 1 nm. Therefore, we can obtain the size of the frequency change in Stokes shift due to the variation from the initial wavelength as an error signal. The wavelength can be stabilized by adjusting the current or temperature of the semiconductor laser to compensate for the error signal. In our experiment, 1-pm wavelength stability was achieved together with a long-term wavelength drift ( > 4 h) of 10 pm.