Abstract

The grating loaded external cavity semiconductor laser is widely used for demonstration of coherent optical fiber communication because of its versatility for tuning and high spectral purity.^[1] For heterodyne application, it is desirable that this laser can be stably and continuously tuned through a broad bandwidth. However, the high laser gain and the large medium nonlinearity limit the expected tuning ability when the antireflection coating on the facet facing the grating is less than perfect. In fact, power variation and optical bistability with respect to tuning are expected.^[2] We present in this paper an experimental study of the power instability and optical bistability, when the grating and cavity length are not tuned synchronously.

© 1987 Optical Society of America