9361646 Lei The proposed will develop an injection laser capable of emitting coherent radiation in the spectral range from the blue to the ultraviolet. A wide bandgap semiconductor will be provided with an asymmetric barrier that will permit injection of minority carriers while blocking the extraction of majority carriers, thus establishing the necessary population inversion. To make this light emitter into an injection laser, the device can be provided with either a Fabry-perot cavity or a superlattice that forms a distributed feedback grating. A simple structure will be made to demonstrate that efficient minority carrier injection can be obtained with resultant emission of short wavelengths. Then the final structure will be designed and the limits of performance will be calculated; obtainable wavelength range, expected efficiency, power handling capability, and far-field pattern. ***
