Abstract: A wavelength-tunable optical transmission apparatus including an optical array unit comprising a plurality of light sources whose wavelengths are changed, an optical driving unit configured to receive an electrical signal transmitted from an external circuit, generate the current and input the generated current to the optical array unit, and a control unit configured to control the magnitude of current input to the optical array unit by controlling the optical driving unit.

Abstract: A laser light generator emits laser light, a frequency of which can be adjusted. A laser light detector bombards an iodine cell with the laser light and photoelectrically converts the laser light that has passed through the iodine cell, then outputs a light output signal. A third order differential lock-in amplifier generates a third order differential signal of the light output signal. A frequency locker causes the laser light generator to change the frequency of the laser light within a predetermined range, detects an amplitude corresponding to a saturated absorption line occurring in the third order differential signal, and causes the frequency of the laser light to stabilize to a predetermined value. An error detector outputs an error signal in a case where the amplitude corresponding to the saturated absorption line occurring in the third order differential signal is greater than a predetermined value.

Abstract: A fiber amplifier is disclosed having a core region embedded within a cladding. The core region further has multiple sections, each of which is doped with at least one rare-earth ion.

Abstract: A discharge-pumped gas laser device may include a laser chamber, a pair of discharge electrodes provided in the laser chamber, a fan with a magnetic bearing being provided in the laser chamber and configured to be capable of circulating a gas in the laser chamber, a housing configured to contain the laser chamber, and a magnetic bearing controller connected to the magnetic bearing electrically, being capable of controlling the magnetic bearing, and provided in the housing separately from the laser chamber.

Abstract: A laser source (340) comprises a first frame (356), a laser (358), and a first mounting assembly (360). The laser (358) generates an output beam (354) that is directed along a beam axis (354A). The first mounting assembly (360) allows the laser (358) to expand and contract relative to the first frame (356) along a first axis and along a second axis that is orthogonal to the beam axis, while maintaining alignment of the output beam (354) so the beam axis (354A) is substantially coaxial with the first axis. The first mounting assembly (360) can include a first fastener assembly (366) that couples the laser (358) to the first frame (356), and a first alignment assembly (368) that maintains alignment of the laser (358) along a first alignment axis (370) that is substantially parallel to the first axis.

Abstract: An optical semiconductor device includes a semiconductor substrate; a lower cladding layer formed over the semiconductor substrate; a quantum well active layer formed on the lower cladding layer; a diffraction grating layer formed over the quantum well active layer and having diffraction gratings formed in a surface thereof; and an upper cladding layer formed on the diffraction gratings of the diffraction grating layer. Further, a band gap in outer regions of the quantum well active layer that are adjacent to outer end surfaces of the optical semiconductor device is greater than the band gap in an inner region of the quantum well active layer that is located between the outer regions, and a thickness of one or more layers, which include the lower cladding layer and positioned between the semiconductor substrate and the quantum well active layer, is greater than or equal to 2.3 ?m.

Abstract: A source of optical supercontinuum radiation comprises a length of microstructured optical fiber and a pump laser, the pump laser adapted to generate lasing radiation having a pump wavelength in the wavelength range of 900 nm to 1200 nm for generating an optical supercontinuum, the length of microstructured optical fibre comprising a core region having a diameter in the range of 1 ?m to 5 ?m and a cladding region which surrounds the core region; the cladding region comprising at least two capillary air holes having substantially the same diameter and which extend substantially along the length of the fibre; the fiber comprising a zero dispersion wavelength within ±200 nm of said pump wavelength; wherein the length of microstructured fiber can support a plurality of modes at said pump wavelength; and wherein said lasing radiation at said pump wavelength is launched into said core region of said length of microstructured optical fiber to excite the fundamental mode of the fiber.

Abstract: A cryogenic cooling apparatus for high average power laser oscillator or amplifier, wherein the oscillator or amplifier material is in direct contact with a flowing cryogenic liquid cooled to below its boiling point is described. This method of cooling overcomes the limit in heat flux due to the onset of film boiling, thereby allowing for increased laser average power.

Abstract: An assembly includes an etalon assembly for dynamically locking a frequency of an optical beam to a set frequency, the etalon assembly being external to a laser source assembly that outputs the optical beam. The etalon assembly includes an etalon that receives the optical beam and generates via interference effects a transmission beam, the etalon having a thermal tuning range greater than one half of a free spectral range of the etalon. The etalon assembly also includes an etalon heater mounted to the etalon such that the etalon heater is configured to adjust the temperature of the etalon. The assembly includes a controller configured to retrieve calibration data based on the set frequency, calculate a set temperature for the etalon using a thermal tuning algorithm and the calibration data, and control the etalon heater such that the etalon has a temperature equal to the calculated set temperature.

Abstract: A vertical cavity surface emitting laser includes: a substrate; a first mirror layer which is provided over the substrate; an active layer which is provided over the first mirror layer; a second mirror layer which is provided over the active layer; a first electrode and a second electrode which are electrically connected to the first mirror layer and are separated from each other; and a third electrode which is electrically connected to the second mirror layer, wherein the first mirror layer, the active layer, and the second mirror layer configure a laminated body, the laminated body includes a resonance portion which resonates light generated in the active layer, in a plan view, an insulation layer surrounding the laminated body is provided, and in the plan view, the insulation layer is provided between the first electrode and the second electrode.

Abstract: A semiconductor laser device includes an n-type clad layer, a first p-type clad layer and a ridge stripe. The device also includes an active layer interposed between the n-type clad layer and the first p-type clad layer, and a current-blocking layer formed on side surfaces of the ridge stripe. The ridge stripe of the device includes a second p-type clad layer formed into a ridge stripe shape on the opposite surface of the first p-type clad layer from the n-type clad layer. The ridge stripe is formed such that a first ridge width as the width of a surface of the second p-type clad layer exists on the same side as the first p-type clad layer and a second ridge width as the width of a surface of the second p-type clad layer exists on the opposite side from the first p-type clad layer.

Abstract: The invention relates to a novel type of gate-tunable photonics and plasmonics which utilizes doped large-scale graphene coupled with ferroelectric material. The graphene-ferroelectric hybrid structure paves the way for the realization of ultra-fast, low power consumption and multi-wavelength operation saturable absorbers for applications in ultra-fast laser systems and novel types of plasmonics for applications in infrared detection, single-photon quantum devices and ultrasensitive detectors.

Abstract: According to an embodiment of the invention, there is provided a micro integratable tunable laser assembly (m-ITLA) which includes an electrical interface for interfacing with a host, a tunable laser module for conducting optical communication, and a control unit, for at least controlling operation of the tunable laser module according to information received from the host via the electrical interface. The m-ITLA can have a length of about 37 mm or less and a width of about 20 mm or less.

Abstract: An arbitrary waveform generator modifies the input signal to a laser diode driver circuit in order to reduce the overshoot/undershoot and provide a “flat-top” signal to the laser diode driver circuit. The input signal is modified based on the original received signal and the feedback from the laser diode by measuring the actual current flowing in the laser diode after the original signal is applied to the laser diode.

Abstract: A laser system includes a seed laser configured to generate a plurality of optical pulses; a controller configured to receive the plurality of the optical pulses and obtain chirped pulses, each chirped pulse having a chirping amount different from each other; an optical waveguide, having a characteristic of anomalous dispersion, configured to cause soliton self-frequency shifts while the chirped pulses propagating so that each center wavelength of a pulse which output from the optical waveguide is different from each other.

Abstract: An optical semiconductor device has: a semiconductor structure; a mesa structure including the semiconductor structure, a p-type semiconductor layer formed on a plane portion, a first side face and a second side face of the mesa structure, and a high-resistance semiconductor layer burying the mesa structure and the p-type semiconductor layer. The first side face is inclined toward a principal surface of the substrate more than the second side face. The p-type semiconductor layer has a carrier concentration in a portion related to the first side face lower than that of a portion related to the plane portion and the second side face. A distance between a lower end of the active layer and a boundary between the first side face and the second face in a vertical direction to the plane portion is not less than 0.1 ?m and not more than 0.5 ?m.

Abstract: A first contact surface of a semiconductor laser chip can be formed to a first target surface roughness and a second contact surface of a carrier mounting can be formed to a second target surface roughness. A first bond preparation layer comprising a first metal can optionally be applied to the formed first contact surface, and a second bond preparation layer comprising a second metal can optionally be applied to the formed second contact surface. The first contact surface can be contacted with the second contact surface, and a solderless securing process can secure the semiconductor laser chip to the carrier mounting. Related systems, methods, articles of manufacture, and the like are also described.

Abstract: An optical device includes a gallium and nitrogen containing substrate comprising a surface region configured in a (20-2-1) orientation, a (30-3-1) orientation, or a (30-31) orientation, within +/?10 degrees toward c-plane and/or a-plane from the orientation. Optical devices having quantum well regions overly the surface region are also disclosed.

Abstract: A laser includes a total reflective mirror, an output mirror, a discharge lamp, and an active laser medium. The total reflective mirror, the output mirror, and the discharge lamp define a resonant cavity. The active laser medium is filled in the resonant cavity. The total reflective mirror includes a body, a metal film, and at least one microstructure. The at least one microstructure is concaved from a first reflective surface of the total reflective mirror. The at least one microstructure has a depth and a lateral size, and both the depth and the lateral size are in a range from about 0.5? to about 2?, while ? is a working wavelength of the laser.

Abstract: A laser includes a total reflective mirror, an output mirror, a discharge lamp, and an active laser medium. The total reflective mirror, the output mirror, and the discharge lamp define a resonant cavity. The active laser medium is filled in the resonant cavity. The total reflective mirror includes a microstructure. The microstructure is convex ring-shaped structure. The convex ring-shaped structure has a height and a width, and both the height and the width are in a range from about 0.5? to about 2?, while ? is a working wavelength of the laser.