Disclosed herein are various embodiments for stronger and more powerful high speed laser arrays. For example, an apparatus is disclosed that comprises an active mesa structure in combination with an electrical waveguide, wherein the active mesa structure comprises a plurality of laser regions within the active mesa structure itself, each laser region of the active mesa structure being electrically isolated within the active mesa structure itself relative to the other laser regions of the active mesa structure.

A surface emitting laser may include an isolation layer including a first center portion and a first plurality of outer portions extending from the first center portion, and a metal layer including a second center portion and a second plurality of outer portions extending from the second center portion. The metal layer may be formed on the isolation layer such that a first outer portion, of the second plurality of outer portions, is formed over one of the first plurality of outer portions. The surface emitting laser may include a passivation layer including a plurality of openings. An opening may be formed over the first outer portion. The surface emitting laser may include a plurality of oxidation trenches. An oxidation trench may be positioned at least partially between the first outer portion and a second outer portion of the second plurality of outer portions.

A vertical cavity surface emitting laser includes a first distributed Bragg reflector, an active layer, and a second distributed Bragg reflector. The first distributed Bragg reflector, the active layer and the second distributed Bragg reflector are arranged in sequence in the direction of a first axis. The second distributed Bragg reflector includes a semiconductor region and a high resistance region. The high resistance region has an electrical resistance higher than the electrical resistance of the semiconductor region. The first axis passes through the semiconductor region. The high resistance region surrounds the semiconductor region. In a cross section including the first axis, the high resistance region has an inner edge extending in a direction inclined with respect to the first axis such that an inner diameter of the high resistance region increases as a distance from the active layer increases in the direction of the first axis.

A laser diode apparatus has a first waveguide layer including a gain region connected in series with a second waveguide layer with a second gain region. A tunnel junction is positioned between the first and second guide layers. A single collimator is positioned in an output path of laser beams emitted from the first and second waveguide layers. The optical beam from the single collimator may be coupled into an optical fiber.

Building blocks are provided for on-chip chemical sensors and other highly-compact photonic integrated circuits combining interband or quantum cascade lasers and detectors with passive waveguides and other components integrated on a III-V or silicon. A MWIR or LWIR laser source is evanescently coupled into a passive extended or resonant-cavity waveguide that provides evanescent coupling to a sample gas (or liquid) for spectroscopic chemical sensing. In the case of an ICL, the uppermost layer of this passive waveguide has a relatively high index of refraction that enables it to form the core of the waveguide, while the ambient air, consisting of the sample gas, functions as the top cladding layer. A fraction of the propagating light beam is absorbed by the sample gas if it contains a chemical species having a fingerprint absorption feature within the spectral linewidth of the laser emission.

A closely spaced emitter array may include a first emitter comprising a first plurality of structures and a second emitter, adjacent to the first emitter, comprising a second plurality of structures. The first emitter and the second emitter may be configured in the closely spaced emitter array such that different types of structures between the first plurality of structures and the second plurality of structures do not overlap while maintaining close spacing between the first emitter and the second emitter.

In some implementations, an emitter may include a substrate and a set of layers on the substrate. The set of layers may include a first mirror, a second mirror that includes a partial reflector and an additional layer, and at least one active region between the first mirror and the second mirror. A first reflectivity of the second mirror at a lateral center of the second mirror may be different than a second reflectivity of the second mirror at a lateral edge of the second mirror.

A light emitting element includes a laminated structure 20 in which a first compound semiconductor layer 21, an active layer 23, and a second compound semiconductor layer 22 are laminated, a first light reflecting layer 41, and a second light reflecting layer 42 having a flat shape, a base surface 90 located on a side of a first surface of the first compound semiconductor layer 21 has a first region 91 (upwardly convex first-A region 91A and first-B region 91B) including a protruding portion protruding in a direction away from the active layer and a second region 92 having a flat surface, the first light reflecting layer 41 is formed at least on the first-A region 91A, a second curve formed by the first-B region 91B and a straight line formed by the second region 92 intersects at an angle exceeding 0°, and the second curve includes at least one kind of figure selected from the group consisting of a combination of a downwardly convex curve, a line segment, and an arbitrary curve.

An emitter may include a substrate, a conductive layer on at least a bottom surface of a trench, and a first metal layer to provide a first electrical contact of the emitter on an epitaxial side of the substrate. The first metal layer may be within the trench such that the first metal layer contacts the conductive layer within the trench. The emitter may further include a second metal layer to provide a second electrical contact of the emitter on the epitaxial side of the substrate, and an isolation implant to block lateral current flow between the first electrical contact and the second electrical contact.

A closely spaced emitter array may include a first emitter comprising a first plurality of structures and a second emitter, adjacent to the first emitter, comprising a second plurality of structures. The first emitter and the second emitter may be configured in the closely spaced emitter array such that different types of structures between the first plurality of structures and the second plurality of structures do not overlap while maintaining close spacing between the first emitter and the second emitter.