Abstract: An apparatus includes a thermoelectric cooler having a first set of one or more metal electrodes, a second set of one or more metal electrodes, and one or more doped semiconductor members. Each member physically joins a corresponding one electrode of the first set to a corresponding one electrode of the second set. Each member has a cross-sectional area that increases along a path from the one metal electrode of the first set to the one metal electrode of the second set.

Abstract: An apparatus includes a thermoelectric cooler having a first set of one or more metal electrodes, a second set of one or more metal electrodes, and one or more doped semiconductor members. Each member physically joins a corresponding one electrode of the first set to a corresponding one electrode of the second set. Each member has a cross-sectional area that increases along a path from the one metal electrode of the first set to the one metal electrode of the second set.

Abstract: An optical device comprises a cavity resonator and an intracavity ridge waveguide. The ridge waveguide includes a monolithically integrated intersubband core region and a nonlinear mixing region (NMR). In response to external pumping energy the core region generates laser light at a first frequency and in a first transverse mode. In response to the laser light the NMR generates parametric light at a second frequency and in a second transverse mode. For phase matching the effective-refractive-index-versus-ridge-width characteristics of the modes of the laser and the parametric light intersect one another at a phase matching width and so that, at greater widths, the effective refractive index of the mode of the higher frequency light is less than that of the lower frequency light. For true phase matching the width of the ridge is made to be essentially equal to the phase matching width.

Abstract: An optical device comprises a cavity resonator and an intracavity ridge waveguide. The ridge waveguide includes a monolithically integrated intersubband core region and a nonlinear mixing region (NMR). In response to external pumping energy the core region generates laser light at a first frequency and in a first transverse mode. In response to the laser light the NMR generates parametric light at a second frequency and in a second transverse mode. For phase matching the effective-refractive-index-versus-ridge-width characteristics of the modes of the laser and the parametric light intersect one another at a phase matching width and so that, at greater widths, the effective refractive index of the mode of the higher frequency light is less than that of the lower frequency light. For true phase matching the width of the ridge is made to be essentially equal to the phase matching width.