1. Introduction
Digital latch can cache information temporarily and is widely used in information processing. With the increase demanding for faster information processing, higher bandwidth optical transmission needs to be applied. Semiconductor laser can transform electrical signals into optical signals, and has high efficiency, high coherence and perfect stability, so it's widely used as electro-optical conversion device [1], [2]. However, the current semiconductor lasers, including surface emitting laser, vertical cavity surface-emitting laser (VCSEL) and so on, can only realize the information loading[2], [3]. The device's output is only decided by the input. Research on lasers that can realize other logic operations has aroused widespread interest.