Ultrahigh frequency optical self-modulator

摘要

Polarization self-modulation of a laser produces high-frequency optical modulation without the use of high-speed electronics. This is accomplished by inserting into a laser cavity a polarization converter, which rotates the polarization of the laser light periodically as the light passes through the converter as it circulates in the cavity. The frequency of the modulation is determined by the cavity length. In one configuration, a quarter-wave retardation plate is used as the intracavity polarization converter in a Fabry-Perot laser. In a second embodiment, the converter is an electro-optic crystal which acts as an electronically-controllable half-wave retardation plate.