Abstract: Surface-emitting semiconductor laser chip (1) comprising a carrier (20), a layer stack (10) arranged on the carrier (20) and having a layer plane (L) extending perpendicularly to the stacking direction (R), a front side contact (310) and a rear side contact (320), in which in operation a predetermined distribution of a current density (I) is achieved by means of current constriction in the layer stack (10), wherein in the carrier (20) an electrical through-connection (200) is provided, which extends from a bottom surface (20a) of the carrier (20) facing away from the layer stack (10) to a surface of the carrier (20) facing the layer stack (10), and the distribution of the current density (I) is significantly influenced by the shape and size of the cross-section of the through-connection (200) parallel to the layer plane (L) on the surface facing the layer stack.

Abstract: This surface-emitting laser device comprises: a first reflective layer; an active region disposed over the first reflective layer; an aperture region which is disposed over the active region and comprises an aperture and an insulating region; a second reflective layer disposed over the aperture region; and a second electrode electrically connected to the second reflective layer. The second electrode comprises first to sixth conductive layers. The first conductive layer may comprises Ti, and the sixth conductive layer may comprise Au.

Abstract: Disclosed is a laser system including a first laser and a second laser. The first laser includes a laser cavity, and a gas phase molecular gain medium disposed in the laser cavity, the gain medium having an absorption band. The second laser is a solid state laser configured to be continuously tunable, with respect to an emission wavelength of the second laser, over the absorption band of the gain medium, and the second laser is tuned to pump rotational vibrational transitions in the gain medium to achieve a rotational population inversion.

Abstract: A coherent beam combination (CBC) system (10) includes an array of beam sources (12a, 12b and 12c) generating coherent beams directed towards a target (T). The phase modulators (14a, 14b and 14c) allow adjustment of relative phase offsets of the beams. A detector (16) monitors an intensity of the radiation impinging on an area of the target (T). A controller (18) receives the intensity parameter and controls a phase adjustment of the beams according to a deterministic (i.e., quantitative) measurement of a phase offset of each beam relative to a representative phase of the sum of all the other beams. This is achieved by using interferometric techniques, referred to herein as Target In-the-Loop Interferometry (TILI).

Abstract: A puncture forming method is a method of forming punctures in a sample by irradiating a surface of the sample with a light beam. The puncture forming method includes: forming a first puncture by irradiating a first position on the surface of the sample with a first pulse of the light beam; and after the forming of the first puncture, forming a second puncture which at least partially overlaps the first puncture by irradiating, with a second pulse of the light beam, a second position on the surface of the sample positioned away from the first position in a first direction. The second puncture has a tip which is positioned inside the sample and which is bent in a direction opposite to the first direction.

Abstract: A VCSEL device includes a substrate and a laser cavity that includes a gain section disposed between first and second reflectors. The VCSEL device is operable to emit light through a first end of the VCSEL device. The VCSEL device includes an anode surface mount contact and a cathode surface mount contact, each which is disposed at a second end of the VCSEL device opposite the first end of the VCSEL device.

Abstract: In a semiconductor laser drive device, a wiring inductance in electrically connecting a semiconductor laser and a laser driver is reduced. The semiconductor laser drive device includes a substrate, the laser driver, and the semiconductor laser. The laser driver is built in the substrate. The semiconductor laser is mounted on one surface of the substrate of the semiconductor laser drive device. Connection wiring electrically connects the laser driver and the semiconductor laser by a wiring inductance of 0.5 nanohenries or less.

Abstract: A driver circuit may include a source, a first circuit path, and a second circuit path. The a first circuit path may be connected to the source and include a first anode pad, a first set of connecting elements to connect the first anode pad to an anode of an optical load, a second anode pad that is separate from the first anode pad, a second set of connecting elements to connect the anode of the optical load to the second anode pad, and a switch. The switch being in a closed state causes current to charge the first set of connecting elements and the second set of connecting elements through the first circuit path. The switch transitioning from the closed state to the open state causes the first set of connecting elements to discharge current through the second circuit path to provide an electrical pulse to the optical load.

Abstract: Disclosed is a submarine network device, comprising a fiber set, a pump laser set, an erbium doped fiber amplifier (EDFA) set, a primary fiber coupler (CPL) set and a secondary CPL set, wherein the primary CPL set comprises N primary CPLs, the secondary CPL set comprises N secondary CPLs, with N being an integer greater than or equal to 3. The fiber set is configured to connect the pump laser set, the primary CPL set, the secondary CPL set and the EDFA set. An input port of each primary CPL in the primary CPL set is at least connected with a pump laser. An output port of each secondary CPL in the secondary CPL set is at least connected with an EDFA. Output ports of each primary CPL in the primary CPL set are respectively connected with two different secondary CPLs that are spaced by a secondary CPL, and input ports of each secondary CPL in the secondary CPL set are respectively connected with two different primary CPLs that are spaced by a primary CPL.

Abstract: A beam shutter is for a laser beam. The beam shutter includes: a reflecting optical unit configured to deflect the laser beam; a holding arm, which is capable of being brought into a release position and a shut-off position and on which the reflecting optical unit is held; a sensor circuit with at least one sensor component arranged between the reflecting optical unit and the holding arm; and an evaluation device, which is configured to interact with the sensor circuit, at least in the shut-off position of the holding arm.

Abstract: The present disclosure generally relates optical amplifier modules. In one form for example, an optical amplifier module includes a booster optical amplifier configured to increase optical power of a first optical signal. The module also includes a preamp optical amplifier configured to increase optical power of a second optical signal and a pump laser optically coupled to the booster optical amplifier and the preamp optical amplifier. The pump laser is configured to provide a booster power to the booster optical amplifier and a preamp power to the preamp optical amplifier, the preamp power is effective to induce a gain in optical power to provide a target optical power of the second optical signal from the preamp optical amplifier, and the booster power is dependent on the preamp power.

Abstract: [Problem] To reduce a filter penalty caused by narrowing of an optical signal band due to optical filters having a multiplexing/demultiplexing function in an optical transmission line between transponder units. [Solution] In an optical transmission system 10A, transponder units 21a to 21n and 22a to 22n connected by optical fibers 14 in which optical filters having a multiplexing/demultiplexing function of an optical signal are interposed include a transmission unit 22 that transmits the optical signal obtained by modulating laser light from a laser light source 34 with an electric signal from a communication apparatus to the optical fibers 14, and a reception unit 23 that receives the optical signal from the optical fibers 14 and converts the received optical signal into an electric signal. The reception unit 23 includes a BER measurement unit that measures a BER, based on a received signal, and feeds the measured BER back to a transmitting side.

Abstract: A device and a method for measuring a thermal load caused by energy transfer upconversion in a laser gain crystal. Increasing the pump power multiple times so that the power meter obtains multiple thresholds for a single-frequency laser; obtaining an average pump threshold of the output laser; obtaining cavity parameters of the single-frequency laser; obtaining thermal focal lengths on the tangential and sagittal planes of the laser gain crystal inside the single-frequency laser; obtaining individual ABCD matrices of the laser system on the tangential and the sagittal planes; obtaining a thermal load at the threshold based on the ABCD transfer matrix of the laser gain crystal on the tangential plane, the ABCD transfer matrix of the laser gain crystal on the sagittal plane, and the average pump threshold of the laser system; obtaining a thermal load caused by ETU at threshold based on the thermal load at the threshold.

Abstract: A semiconductor light emitting device includes a microstrip substrate with a single-ended transmission line on a top surface, wherein the single-ended transmission line extends from a first end portion to a second end portion, the microstrip substrate has a ground plane on a bottom surface, and the ground plane is opposed and bonded to the conductive pattern. The single-ended transmission line includes a first section and a second section, wherein the second section extends from the first section and includes the second end portion. The second section is lower in characteristic impedance than the first section. A load circuit that includes the wire, the optical modulator, and the termination resistor is electrically connected between the second end portion and the conductive pattern. The load circuit is equal to or lower in the characteristic impedance than the second section.

Abstract: A method of operating an optoelectronic device comprising an optical waveguide section, the optical waveguide section comprising a semiconductor core, the method comprising the steps of determining (401) a range for a negative bias voltage for the waveguide section for which an optical loss of the core is lower than an optical loss at zero bias for an operating wavelength range of the device, selecting (402) a bias voltage within the range and applying (403) the selected bias voltage to the waveguide section.

Abstract: An optical apparatus comprises a semiconductor substrate, and a supermode filtering waveguide (SFW) emitter disposed on the semiconductor substrate. The SFW emitter comprises a first optical waveguide, a spacer layer, and a second optical waveguide spaced apart from the first optical waveguide by the spacer layer. The second optical waveguide is evanescently coupled with the first optical waveguide and is configured, in conjunction with the first waveguide, to selectively propagate only a first mode of a plurality of optical modes. The SFW emitter further comprises an optically active region disposed in one of the first optical waveguide and the second optical waveguide.

Abstract: The present disclosure discloses a saturable absorber mirror of a composite structure, including: a substrate; a buffer layer on the substrate; a distributed Bragg reflective mirror on the buffer layer; a quantum dot or quantum well saturable absorber body on the distributed Bragg reflective mirror; a graphene saturable absorber body on the quantum dot or quantum well saturable absorber body. In the present disclosure, the graphene saturable absorber body is composited with the quantum dot saturable absorber body or the quantum well saturable absorber body to be used as the saturable absorber body in the saturable absorber mirror of the present disclosure. A thermal damage threshold and an optical property stability of the saturable absorber body are improved, and an ultrafast laser pulse with high power and short pulse mode locking, a stable output repetition cycle, a narrow pulse width, and a short response time is implemented.

Abstract: The invention relates to a method for modulating the resonant frequency of an optical resonator (1) in accordance with a periodic, not necessarily harmonic, modulation signal (Umod(t)). Fast modulation of an optical resonator is intended to be made possible in which the current resonant frequency follows the modulation signal (Umod(t)) as precisely as possible, and specifically at a fundamental frequency of the modulation signal in the kHz range. To do this, the invention proposes the following method steps: deriving an error signal (E(t)) from a light field circulating in the resonator (1), wherein the error signal (E(t)) indicates the deviation of the optical frequency of the light field from a target value, deriving a first actuating signal (S1(t)) from the error signal (E(t)) by means of a controller (6), generating a second actuating signal (S2(t)), which has actuating-signal components at one or more harmonics (fmod, 2fmod, . . .

Abstract: A method and a system are provided to simultaneously generate blue-shifted and red-shifted femtosecond light sources with tunable spectral peak location and bandwidth, by controlling the input condition (chirp/spectrum) of a fiber-optic nonlinear propagation. The system comprises (A) a seed source, (B) a driving current controller to regulate the spectrum of the seed source, (C) a dispersion controller to control the chirp and pulse width of the seed source, (D) a fiber-optic spectral conversion module to shape and broaden the laser spectrum via fiber-optic nonlinear processes, and (E) a spectral selection module to filter out the required wave packets. With the simultaneous uses of the driving current controller and the dispersion controller, the light sources feature continuously tunable spectral peak with (1) a relatively constant output pulse energy or (2) a tunable spectral bandwidth at a specific peak location.

Abstract: Methods, devices, and systems for laser diode packaging platforms are provided. In one aspect, a laser diode assembly includes a heat sink and a plurality of laser diode units horizontally spaced apart from one another on the heat sink. Each laser diode unit includes: a first submount positioned on the heat sink and spaced apart from adjacent another first submount, a laser diode including an active layer between a first-type doped semiconductor layer and a second-type doped semiconductor layer, a bottom side of the laser diode being positioned on the first submount, and a second submount positioned on a top side of the laser diode and spaced apart from adjacent another second submount. The first submount, the laser diode, and the second submount in the laser diode unit are vertically positioned on the heat sink. The laser diodes of the plurality of laser diode units are electrically connected in series.