Abstract: The disclosure describes aspects of laser cavity repetition rate tuning and high-bandwidth stabilization of pulsed lasers. In one aspect, an output optical coupler is described that includes a cavity output coupler mirror, a piezoelectric actuator coupled to the cavity output coupler mirror, a locking assembly within which the cavity output coupler mirror and the piezoelectric actuator are positioned, and one or more components coupled to the locking assembly. The components are configured to provide multiple positional degrees of freedom for tuning a frequency comb spectrum of the pulsed laser (e.g., tuning a repetition rate) by adjusting at least one position of the locking assembly with the cavity output coupler mirror. A method of adjusting an output optical coupler in a pulsed laser is also described. These techniques may be used in different applications, including quantum information processing.

Abstract: The present invention provides an active fiber package for use in a fiber laser, amplifier, or ASE source comprising: a plate-shape base comprising a groove having a configuration of at least two spirals for receiving and fixedly holding an active fiber therein, said at least two spirals are coplanar enabling visibility of said active fiber, the outer loop of one spiral transitioning smoothly to the outer loop of another spiral, and the inner loop of each one of said spirals transitioning smoothly into a relatively short straight section; wherein a portion of said straight section of one of said spirals spliced to a coupling fiber, and wherein multiple inner loops of each one of said spirals in proximity to said straight section having a relatively low radius of curvature for enabling tight coiling of said active fiber, thus, for reducing thermal modal instability (TMI) and increasing lasing power.

Abstract: A semiconductor laser is disclosed. Trim loss region is provided in inner ridge region of surface of transmission layer facing away from substrate, blind hole is provided in trim loss region, and distance from bottom surface of blind hole to surface of second cladding layer facing to substrate is smaller than evanescent wave length in transmission layer. Blind hole can affect optical field characteristics of light transmission in semiconductor laser by affecting evanescent wave. A method for fabricating a semiconductor laser is also provided.

Abstract: An electrically pumped photonic-crystal surface-emitting lasers with optical detector comprises plurality of air holes, by the variation of position and size proportion form a photonic crystal having main structure and sub structure, and produces an optical detection signal by light guiding proportion of the light guiding tunnel, further have power proportion of the laser by reading the strength of the optical detection signal, so the automatic power control circuit can feedback the power proportion for controlling the surface-emitting laser.

Abstract: Quantum well designs for tunable VCSELs are disclosed that are tolerant of the wavelength shift. Specifically, the active region has even number of substantially uniformly spaced (¼ of the center wavelength in the semiconducting material) quantum wells.

Abstract: Embodiments of the disclosure pertain to an optical transmitter comprising a laser configured to generate an optical signal from a single-ended electrical signal, a housing or (sub)assembly containing the laser, a driver configured to generate the single-ended electrical signal, a direct current (DC) return path, and an alternating current (AC) return path. The laser has a DC power pin, and the DC power has a DC component and an AC component. The driver has a first impedance at a first output through which the single-ended electrical signal passes. The housing or (sub)assembly has a second impedance matching the first impedance. The DC return path comprises an inductor and is configured to carry or conduct the DC component of the DC power from the laser (e.g., to an input pin on the driver). The AC return path is configured to carry or conduct the AC component of the DC power from the laser. Methods of using and manufacturing the same are also disclosed.

Abstract: A laser device includes a first laser medium and a second laser medium that have a first surface and a second surface opposite to the first surface, and receive input of excitation light and seed light from the first surface side to amplify the seed light, a holder that holds the first laser medium and the second laser medium; and a pair of cooling units that cool the first laser medium and the second laser medium according to change in volume of a refrigerant.

Abstract: A wavelength combining laser apparatus includes: a semiconductor laser emitting laser beams in an optical-axial direction perpendicular to a laser beam combining direction; a wavelength combining element combining the laser beams in the laser beam combining direction into a single laser beam; a cross-coupling reduction optical system having positive power in the laser beam combining direction perpendicular to an optical axis of the single laser beam output from the wavelength combining element; and a partially-reflective mirror reflecting the single laser beam having passed through the cross-coupling reduction optical system and also allowing the single laser beam to transmit through and exit the partially-reflective mirror.

Abstract: A semiconductor laser source including a Mach-Zehnder interferometer including first and second arms. Each of these arms being divided into a plurality of consecutive sections. The first and second arms each include a gain-generating section forming first and second gain-generating waveguides, respectively. The laser source includes power sources able to deliver currents through the gain-generating waveguides such that the following condition is met: ? n = 1 N 2 ? L 2 , n ? neff 2 , n - ? n = 1 N 1 ? L 1 , n ? neff 1 , n = k f ? ? Si where: kf is a preset integer number higher than or equal to 1, N1 and N2 are the numbers of sections in the first and second arms, respectively, L1,n and L2,n are the lengths of the nth sections of the first and second arms, respectively, neff1,n and neff2,n are the effective indices of the nth sections of the first and second arms, respectively.

Abstract: An integrated semiconductor optical amplifier-laser diode (SOA-LD) device includes a laser diode (LD) section fabricated on a substrate, a semiconductor optical amplifier (SOA) section fabricated on the substrate adjacent to the LD section; and a trench formed at least partially between the LD section and SOA section to electrically isolate the LD section and the SOA section while maintaining optical coupling between the LD section and the SOA section.

Abstract: A heat sink comprising a heat spreader (2) made from synthetic diamond and having a front surface for mounting one or more components to be cooled like a laser disc (8) and a rear surface for direct fluid cooling (10). A plurality of ribs (4,7) is bonded to the rear surface of the heat spreader (2) to stiffen the heat spreader. Both the heat spreader and the plurality of ribs are formed of synthetic diamond material. The ribs (4,7) may be fixed to the heat spreader by braze bonds (6).

Abstract: In a semiconductor laser device that includes: a semiconductor laser element that outputs light from an output portion; and a metal stem that holds the semiconductor laser element, the metal stem includes a base that has a reference surface on an upper surface and a protrusion portion that protrudes upward from the reference surface, and the protrusion portion is provided with an installation surface on which the semiconductor laser element is installed and a side surface which is disposed on an identical plane with a part of an outer circumferential surface of the base.

Abstract: The present disclosure provides a dark cavity laser, including: a frequency stabilized laser output device configured to generate a laser light, and perform a frequency stabilized processing on the generated laser light to output it to the dark cavity laser device as a pump light of a gain medium of a dark cavity; and a dark cavity laser device including a main cavity, and a cavity of the main cavity is provided inside with a gas chamber of a gain medium of a dark cavity laser light, where the gain medium of the dark cavity laser light is alkali metal atoms; the dark cavity laser device is configured to receive the pump light, and form a polyatomic coherent stimulated radiation between transition levels of the alkali metal atoms in the gas chamber by a weak feedback of the main cavity to generate the dark cavity laser light.

Abstract: A semiconductor layer structure may include a substrate, a buffer layer formed on the substrate, and a set of epitaxial layers formed on the buffer layer. The buffer layer may have a thickness that is greater than 2 micrometers (?m). The set of epitaxial layers may include a quantum well layer. A quantum well intermixing region may be formed in association with the quantum well layer and a material diffused from a region of a surface of the semiconductor layer structure.

Abstract: A surface-emitting laser according to an embodiment of the present disclosure includes a current constriction region having an opening and formed by impurities injected into a laminate from side of a second semiconductor layer; and a first DBR layer on side of a first semiconductor layer and a second DBR layer on the side of the second semiconductor layer having the laminate interposed therebetween at a position facing the opening. At the opening, an opening diameter close to the first DBR layer is larger than an opening diameter close to the second DBR layer.

Abstract: A laser pulse generator includes a pulse shape generation device and a clock unit. The generation device includes a pulse shape repository, a digital-to-analog converter (DAC), a first terminal for connecting a start signal line, a second terminal for connecting a clock signal line, and a third terminal for connecting a pulse line. The first and second terminals are connected to the pulse shape repository and the DAC such that when a predefined start signal is present, data is transferred from the pulse shape repository to the DAC and converted by the DAC into an output pulse, for example, at a rate of a clock signal. The output pulse is supplied at the third terminal for actuating a driver of a laser diode. The clock unit is connected to the second terminal via the clock signal line and includes a reset terminal connected to the start signal line.

Abstract: A semiconductor laser diode is disclosed. In an embodiment a semiconductor laser diode includes a semiconductor layer sequence including an active layer having a main extension plane, configured to generate light in an active region during operation and configured to radiate the light via a light-outcoupling surface, wherein the active region extends from a rear surface opposite the light-outcoupling surface to the light-outcoupling surface along a longitudinal direction in the main extension plane and a continuous contact structure directly disposed on a surface of the semiconductor layer sequence, wherein the contact structure comprises in at least a first contact region a first electrical contact material in direct contact with the surface region and in at least a second contact region a second electrical contact material in direct contact with the surface region, and wherein the first and second contact regions adjoin one another.

Abstract: A semiconductor laser tuned with an acousto-optic modulator. The acousto-optic modulator may generate standing waves or traveling waves. When traveling waves are used, a second acousto-optic modulator may be used in a reverse orientation to cancel out a chirp created in the first acousto-optic modulator. The acousto-optic modulator may be used with standing-wave laser resonators or ring lasers.

Abstract: A fiber amplification system is provided for amplifying a laser pulse signal, e.g., an oscillator signal of an oscillator device. The fiber amplification system includes a fiber pre-amplification system having a short, fundamental-mode and step-index fiber configured to pre-amplify the laser pule signal to generate a seed signal and a main amplification system having a large core fiber configured to amplify the seed signal. The short, fundamental-mode step-index fiber can have a length no longer than about 30 cm, and a mode field diameter no less than about 30 ?m, e.g., in a range from 30 ?m to 60 ?m, as well as a high doping concentration needed to provide an absorption length no more than about 30 cm, for providing the seed signal for the large core fiber with low non-linearity.

Abstract: The present disclosure relates, generally, to lasers and, more particularly, to lasers with a setback aperture. In one in illustrative embodiment, a laser comprises front and rear resonator mirrors, an output window positioned near the front resonator mirror, and a plurality of waveguide walls extending between the front and rear resonator mirrors and extending between the rear resonator mirror and an aperture defined by the plurality of waveguide walls, such that a laser beam formed between the front and rear resonator mirrors will propagate in free-space between the aperture and the output window so that a first cross-sectional profile of the laser beam at the aperture will be different than a second cross-sectional profile of the laser beam at the output window.