An edge emitting laser (EEL) device includes a substrate, an n-type buffer layer, a first n-type cladding layer, a grating layer, a spacer layer, a lower confinement unit, an active layer, an upper confinement unit, a p-type cladding layer, a tunnel junction layer and a second n-type cladding layer sequentially arranged from bottom to top. The tunnel junction layer can stop an etching process from continuing to form the second n-type cladding layer into a predetermined ridge structure and converting a part of the p-type cladding layer into the n-type cladding layer to reduce series resistance of the EEL device. Therefore, the optical field and active layer tend to be coupled at the middle of the active layer, the lower half of the active layer can be utilized effectively, and the optical field is near to the grating layer to achieve better optical field/grating coupling efficiency and lower threshold current.

A vertical cavity surface emitting laser (VCSEL) device includes a substrate, a first mirror layer, an active layer, an oxide layer, a second mirror layer, a tunnel junction layer and a third mirror layer sequentially stacked with one another. The first mirror layer and the third mirror layer are N-type distributed Bragg reflectors (N-DBR), and the second mirror layer is P-type distributed Bragg reflector (P-DBR). The tunnel junction layer is provided for the VCSEL device to convert a part of the P-DBR into N-DBR to reduce the series resistance of the VCSEL device, and the tunnel junction layer is not used as current-limiting apertures. This disclosure further discloses a VCSEL device manufacturing method with the in-situ and one-time epitaxy features to avoid the risk of process variation caused by moving the device into and out from an epitaxial cavity.

A laser diode including a double heterostructure comprising a top layer, a buffer layer formed on a substrate, and an intrinsic active layer formed between the top layer and the buffer layer. The top layer and the buffer layer have opposite types of conductivity. The active layer has a bandgap smaller than that of the buffer layer or the top layer. The double heterostructure includes Ge, SiGe, GeSn, and/or SiGeSn materials.

A method of generating a light-matter hybrid species of charged polaritons at room temperature includes providing an organic semiconductor microcavity being a doped organic semiconductor sandwiched in a microcavity capable of generating an optical resonance and coupling light to the polaron optical transition in the organic semiconductor microcavity thereby forming polaron-polaritons. The doped organic semiconductor may be a hole/electron transport material having a polaron absorption coefficient exceeding 10.sup.2 cm.sup.−1 and capable of generating a polaron optical transition with a linewidth smaller than a predetermined threshold. The optical resonance of the microcavity has a resonance frequency matched with the polaron optical transition.

A semiconductor laser according to one embodiment of the present disclosure includes a semiconductor stack. The semiconductor stack includes, in the following order, a first cladding layer, an active layer, one or a plurality of low-concentration impurity layers, a contact layer, and a second cladding layer that includes a transparent conductive material. The semiconductor stack further has, in a portion including the contact layer, a ridge extending in a stacked in-plane direction. Each low-concentration impurity layer has an impurity concentration of 5.0×10.sup.17 cm.sup.−3 or less, and a total thickness of the low-concentration impurity layer is 250 nm or more and 1000 nm or less. A distance between the second cladding layer and the low-concentration impurity layer closest to the second cladding layer is 150 nm or less.

A method of producing an ultraviolet laser diode with a low oscillation threshold current density includes stacking a first cladding layer, a light-emitting layer, and a second cladding layer on a substrate in this order to form a nitride semiconductor laminate (step S101), etching at least a portion of the nitride semiconductor laminate to form a mesa structure and setting the ratio between the length of the resonator end faces and the length of the side surfaces of the mesa structure in plan view between 1:5 and 1:500 (step S102), disposing first conductive material on a portion of a first area and applying heat treatment of 400° C. or higher to form a first electrode (step S103), and disposing a second conductive material in an area on the second cladding layer, at a distance of 5 um or more from the side surfaces, to form a second electrode (step S104).

Included is a semiconductor multilayer film in which a non-doped InAlN layer and a GaN layer formed on said InAlN layer and containing a dopant are stacked a plurality of times.

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.

An embodiment relates to a surface-emitting laser element, a light-emitting device comprising same, and a method for manufacturing same. A surface-emitting laser element according to an embodiment may comprise: a substrate; a first reflective layer disposed on the substrate; an active layer disposed on the first reflective layer; an aperture region disposed on the active layer and including an aperture and an insulation region; and a second reflective layer disposed on the aperture region. The doping level of the aperture region may be (X+3)XXE18(atoms/cm.sup.3) A ratio (b/a) of a second minimum diameter (b) to a first maximum diameter (a) of the aperture may be [95.0−(2X/3)]% to [99.9−(X/3)]%, wherein X may be 0 to 3.

A semiconductor vertical light source includes upper and lower mirrors with an active region in between, an inner mode confinement region, and an outer current blocking region that includes a common epitaxial layer including an epitaxially regrown interface between the active region and upper mirror. A conducting channel including acceptors is in the inner mode confinement region. The current blocking region includes a first impurity doped region with donors between the epitaxially regrown interface and active region, and a second impurity doped region with acceptors between the first doped region and lower mirror. The outer current blocking region provides a PNPN current blocking region that includes the upper mirror or a p-type layer, first doped region, second doped region, and lower mirror or an n-type layer. The first and second impurity doped region force current flow into the conducting channel during normal operation of the light source.