Abstract: A method is presented for fabricating a semiconductor device operable to generate a THz spectral range radiation in response to an external field. According to this method, a heterostructure is formed from selected layers. The layers include at least first and second semiconductor layers made of materials having a certain initial overlap between the valence band of the second layer material and the conduction band of the first layer material. The heterostructure layers are arranged with a selected layout providing a quantum mechanical coupling between an electron quantum well (EQW) in said first layer and a hole quantum well (HQW) in said second layer. The layout is selected so as to define a predetermined arrangement of a plurality of energy subbands and a predetermined dispersion of these subbands to define a desired effective overlap between the energy subbands of said conduction and valence bands.

Abstract: A method is presented for fabricating a semiconductor device operable to generate a THz spectral range radiation in response to an external field. According to this method, a heterostructure is formed from selected layers. The layers include at least first and second semiconductor layers made of materials having a certain initial overlap between the valence band of the second layer material and the conduction band of the first layer material. The heterostructure layers are arranged with a selected layout providing a quantum mechanical coupling between an electron quantum well (EQW) in said first layer and a hole quantum well (HQW) in said second layer. The layout is selected so as to define a predetermined arrangement of a plurality of energy subbands and a predetermined dispersion of these subbands to define a desired effective overlap between the energy subbands of said conduction and valence bands.

Abstract: A semiconductor device and method of its fabrication are provided to enable the device operation in a THz spectral range. The device comprises a heterostructure including at least first and second semiconductor layers. The first and second layers are made of materials providing a quantum mechanical coupling between an electron quantum well (EQW) in the first layer and a hole quantum well (HQW) in the second layer, and providing an overlap between the valence band of the material of the second layer and the conduction band of the material of the first layer. A layout of the layers is selected so as to provide a predetermined dispersion of energy subbands in the conduction band of the first layer and the valence band of the second layer.

Abstract: A semiconductor device and method of its fabrication are provided to enable the device operation in a THz spectral range. The device comprises a heterostructure including at least first and second semiconductor layers. The first and second layers are made of materials providing a quantum mechanical coupling between an electron quantum well (EQW) in the first layer and a hole quantum well (HQW) in the second layer, and providing an overlap between the valence band of the material of the second layer and the conduction band of the material of the first layer. A layout of the layers is selected so as to provide a predetermined dispersion of energy subbands in the conduction band of the first layer and the valence band of the second layer.

Abstract: A semiconductor laser device which operates stably at high power in the lowest order lateral mode is disclosed. Stable operation in the lowest order lateral mode is achieved by coupling the laser to a particular resonant mode of a Fabry-Perot resonator oriented perpendicular to the laser. Coupling between the laser and the resonator is illustratively achieved through use of an optical integrated circuit comprising two grating structures oriented orthogonally to each other.