Polycrystalline Optical Waveguide Isolator

Semiconducting lasers, laser arrays and other diode-laser devices for both military and private sector applications benefit greatly if used in conjunction with isolators capable of preventing reflections from reentering the device. This proposal describes an approach which can be integrated with laser/amplifier semiconducting material system, to produce efficient non-reciprocal magneto-optic isolators. The method is based on the use of Faraday rotation in ferromagnetic metal films. The isolator(s) may be monolithically integrated with diode lasers, amplifiers, arrays, switches, and modulators to give far superior performance to present state-of-the-art devices. Isolators integrated with diode-laser devices will find extensive use in all applications using diode lasers. Civilian and military fiber and space communication devices lidars and other military and civilian applications requiring stable-high-power-coherent radiation from compact efficient sources will all benefit from the availability of monolithically integrated isolators.