Innovative switching mechanism improves ultrafast control of microlasers

The all-optical switch is a kind of device that controls light with light, which is the fundamental building block of modern optical communications and information processing. Creating an efficient, ultrafast, and compact all-optical switch has been recognized as the key step for the developments of next-generation optical and quantum computing. In principle, photons don't interact with one another directly in the low power linear regime, and a cavity is usually needed to resonantly enhance the field of control light and increase the interaction. In early work, the performance of all-optical switches has been improved rapidly by optimizing resonators such as microrings or photonic crystals. For further improvements, the research area reaches the limit—the trade-off between ultralow energy consumption and ultrashort switching time.