Abstract: A vertical cavity surface emitting laser (VCSEL) device comprising a VCSEL emitter having a waveguide with a guided portion and an antiguided portion is disclosed. The guided and antiguided portions may select and confine a mode of the VCSEL emitter. The antiguided portion may also be used to coherently couple adjacent VCSEL emitters.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: A vertical cavity surface emitting laser (VCSEL) array fabricated to produce multiple wavelengths. A first distributed Bragg reflector (DBR) is formed on a substrate, and an optical cavity having an active region and a cavity layer is formed on the first DBR, and a second DBR is formed on the optical cavity. The cavity layer is selectively etched to form wavelength-specific regions having different filling factors. As a result, the wavelength-specific regions have different optical thicknesses (e.g., different refractive indexes and/or physical thicknesses) and generate different Fabry Perot wavelengths.

Abstract: This disclosure describes a method of forming a VCSEL with a structural birefringent cavity. This method comprises growing a bottom distributed Bragg reflector (DBR) and a first part of a cavity on a substrate to form a bottom structure comprising a plurality of layers. One or more anisotropic features are etched on a upper layer of the bottom structure to produce a patterned growth interface. A remaining part of the cavity and a top DBR on the patterned growth interface are overgrown to form an epitaxial structure. One or more oxide apertures are formed in the epitaxial structure.

Abstract: A vertical cavity surface emitting laser (VCSEL) array is fabricated to produce multiple wavelengths. A first distributed Bragg reflector (DBR) is formed on a substrate, and an optical layer having an active region is formed on the first DBR. The optical layer has a variation in optical characteristic configured to generate multiple wavelengths. To do this, a first portion of the layer is formed on the first DBR. Different dimensioned features (profiles, wells, trenches, gratings, etc.) are then formed on a surface of the first portion. Subsequently, a second portion of the layer is formed by filling in the dimensioned features on the first portion's surface. Finally, a second DBR is formed on the second portion of the layer. The variation in optical characteristic can include variation in refractive index, physical thickness, or both. The assembly can be processed as usual to produce a VCSEL array having multiple emitters.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: An edge-emitting GaAs-based semiconductor laser uses a tunnel junction in combination with an inverted p-n junction to address oxidation problems associated with the use of a high aluminum content p-type cladding arrangement. In particular, a tunnel junction is formed on an n-type GaAs substrate, with p-type cladding and waveguiding layers formed over the tunnel junction. N-type waveguiding and cladding layers are thereafter grown on top of the active region. Since the p-type layers are positioned below the active region and not exposed to air during processing, a relative high aluminum content may be used, which improves the thermal and electrical properties of the device. Since the n-type material does not require a high aluminum content, it may be further processed to form a ridge structure without introducing any substantial oxidation of the structure.

Abstract: A fiber amplifier to amplify seed light has a laser diode, an optical fiber segment, and a doped fiber. The laser diode generates pump light at a pump wavelength from an end facet, and optical fiber segment in optical communication with the pump light has a fiber Bragg grating (FBG) configured to lock the pump light from the end facets to the pump wavelength. The pump light from the laser diode interact with an active dopant of the doped fiber and can thereby amplifies the seed light. To provide less coherent light and improve stability of the laser diode over operation conditions, variations in refractive index in the FBG have a chirped period changing linearly along a length of the FBG. The chirped period shifts the reflectivity asymmetrically from a central wavelength region of the FBG, such as blue-shifting the reflectivity for a short wavelength.

Abstract: A semiconductor laser is formed to include a current blocking layer that is positioned below the active region of the device and used to minimize current spreading beyond the defined dimensions of an output beam's optical mode. When used in conjunction with other current-confining structures typically disposed above the active region (e.g., ridge waveguide, electrical isolation, oxide aperture), the inclusion of the lower current blocking layer improves the efficiency of the device. The current blocking layer may be used in edge-emitting devices or vertical cavity surface-emitting devices, and also functions to improve mode shaping and reduction of facet deterioration by directing current flow away from the facets.

Abstract: A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.

Abstract: A vertical cavity surface emitting laser (VCSEL) array is fabricated to produce multiple wavelengths. A first distributed Bragg reflector (DBR) is formed on a substrate, and an optical layer having an active region is formed on the first DBR. The optical layer has a variation in optical characteristic configured to generate multiple wavelengths. To do this, a first portion of the layer is formed on the first DBR. Different dimensioned features (profiles, wells, trenches, gratings, etc.) are then formed on a surface of the first portion. Subsequently, a second portion of the layer is formed by filling in the dimensioned features on the first portion's surface. Finally, a second DBR is formed on the second portion of the layer. The variation in optical characteristic can include variation in refractive index, physical thickness, or both. The assembly can be processed as usual to produce a VCSEL array having multiple emitters.

Abstract: A laser device having a semiconductor gain element optically coupled to an optical fiber by using an angled anamorphic fiber lens and including a wavelength-selective front reflector. The laser device possesses improved output characteristics such as a highly linear laser emission output, even when the amplification section produces a high amount of gain. Such a laser source can also be used in various applications such as pump lasers for fiber amplifiers or frequency doubling systems.

Abstract: A laser device having a semiconductor gain element optically coupled to an optical fiber by using an angled anamorphic fiber lens and including a wavelength-selective front reflector. The laser device possesses improved output characteristics such as a highly linear laser emission output, even when the amplification section produces a high amount of gain. Such a laser source can also be used in various applications such as pump lasers for fiber amplifiers or frequency doubling systems.