Abstract: Semiconductor device structures comprising laser diode cavities with at least one of a mode-selective filter and a phase-alignment element, and methods for their fabrication, are disclosed. An example device structure comprises a surface-etched grating distributed-feedback (SEG DFB) laser with a mode-selective reflector structure. The reflector structure is designed to provide higher pot feedback of the fundamental TE0 mode and suppression of higher order mode effects. The reflector structure may be a single interface (single facet) mirror type reflector comprising a spatially patterned reflector, or a multi-interface distributed Bragg reflector (DBR). A phase alignment element may be included to provide precise optical phase control. A photodetector for back-facet power monitoring may be included. A method of fabrication is disclosed, based on a self-aligned process in which DBR features are included on the same mask that is used for the DFB laser grating.

Abstract: A method of wavelength conversion includes receiving a modulated optical signal of a first wavelength and using the modulated optical signal to optically pump an active medium to generate and transmit a like modulated optical signal of a second wavelength, all of which is affected entirely within an optical domain without electrical contacts. Also, an optical wavelength converter includes an active medium that is optically pumped by a modulated optical signal of a first wavelength and transmits the modulated optical signal at a second wavelength. The active medium may be contained in a detachable, external module for wavelength conversion of a fixed wavelength source.

Abstract: The invention features an edge-emitting semiconductor signal laser having an active region to produce laser light. There is provided a semiconductor pump laser monolithically integrated with the edge-emitting signal laser. The pump laser includes a photon emissive active region to provide photopumping of the active region of the edge-emitting signal laser, thereby providing optical excitation of the active region of the signal laser.

Abstract: A method of wavelength conversion includes receiving a modulated optical signal of a first wavelength and using the modulated optical signal to optically pump an active medium to generate and transmit a like modulated optical signal of a second wavelength, all of which is affected entirely within an optical domain without electrical contacts. Also, an optical wavelength converter includes an active medium that is optically pumped by a modulated optical signal of a first wavelength and transmits the modulated optical signal at a second wavelength. The active medium may be contained in a detachable, external module for wavelength conversion of a fixed wavelength source.

Abstract: The invention features an edge-emitting semiconductor signal laser having an active region to produce laser light. There is provided a semiconductor pump laser monolithically integrated with the edge-emitting signal laser. The pump laser includes a photon emissive active region to provide photopumping of the active region of the edge-emitting signal laser, thereby providing optical excitation of the active region of the signal laser.

Abstract: An optically pumped monolithic VCSEL (vertical cavity surface emitting laser) architecture is disclosed. The laser structure comprises at least one signal VCSEL, at least one pump laser, and transition regions between the signal VCSELs and the pump lasers The signal VCSEL is laterally optically pumped by the pump laser, which can be electrically or optically pumped. The signal VCSEL, the pump laser and the transition region all are monolithically integrated onto a common substrate. The signal VCSEL can be disposed outside or inside the pump laser cavity (extra-cavity or intra-cavity pumping). The cavity of the pump laser can takes various forms, such as a concave cavity, a confocal cavity, or a cylindrical or ellipsoidal form of cavity. Several signal VCSEL can be disposed in the focus or focal area of the cavity of the pump laser.

Abstract: In novel sampling methods and apparatus, a repetitive waveform is sampled at a sampling phase which alternates at a phase alternation frequency between a fixed reference phase and a variable phase while changing the variable phase progressively and periodically. The amplitude of a component of the resulting signal at the phase alternation frequency is detected to derive a lower frequency analog of the sampled waveform. The sampling methods and apparatus are particularly useful for electro-optic sampling of very high frequency waveforms in semiconductor devices.

Abstract: A phase-locked linear laser array has an output array in which equispaced optical gain elements are formed along a semiconductor bar and a control laser array having equispaced laser elements in close coupling with the output array. The output array elements, having twice the spacing of the control array elements, are aligned with alternating elements of the control array. The tendency of the control array lasers to operate with 180.degree. optical phase difference between adjacent lasers causes every other laser to be in-phase and thus adjacent elements of the output array are also in-phase.