摘要 |
A distributed feedback heterostructure semiconductor laser provides a single frequency at high power by having a wide output facet so that the power density at the output facet is low enough to avoid catastrophic optical mirror damage. Oscillation is obtained in the center of a pumped trapezoidal gain medium layer between the wide output facet and a relatively narrow rear facet. Stimulated emission of radiation in the balance of the pumped trapezoidal area produces high power output. At the opposite end of the gain layer from the output facet, a parallel edged, index guided pumped region of the gain layer provides a single transverse mode wave guide. A distributed feedback grating, preferably in the region with parallel sides, selects a single longitudinal oscillation mode independent of Fabry-Perot oscillation between the facets. Preferably, the output facet is anti-reflective for minimizing Fabry-Perot oscillation. Alternatively, the grating can be in an unpumped area aligned with the pumped area as a distributed Bragg reflector.
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