Abstract: A holder and at least one terminal element that are configured and arranged with respect to one another so as to form a cavity of length ?L bounded axially by two walls the relative position of which with respect to each other varies in the opposite direction to the variation in ambient temperature, an increase in temperature causing the walls to move closer together and vice versa. A linear structure incorporating the device sees its length decrease when temperature increases and vice versa. Electro-optical transducers comprising a piezoelectric actuator of linear structure that acts on the length of a segment of optical fiber that forms the laser source of the transducer, and having such a device incorporated into the actuator in order to compensate, by modifying the length of the segment of fiber, for the variations in wavelength induced in the laser by the variations in temperature.

Abstract: A problem with a conventional waveguide type laser device is that in the case in which an isotropic laser medium is used for a core, linearly polarized light is not provided. A ridge waveguide laser device of the present disclosure includes: a substrate; a core joined to the substrate and having a laser medium, the core having a refractive index higher than that of the substrate; and a cladding joined to the core, constituting a ridge waveguide together with the core, and made from a birefringent material having ordinary and extraordinary refractive indices lower than the refractive index of the core, the ordinary and extraordinary refractive indices being different.

Abstract: A method of inducing light losses at a parasitic wavelength in a fiber laser system includes providing a wavelength discriminator (WD) spaced from and between feeding and process fibers or from the end output of the feeding fiber so as to induce losses of light at parasitic wavelength. The device implementing the disclosed method is configured with a laser source, the delivery fiber and WD spaced at a distance between the surface to be treated and the end of the delivery fiber, wherein the WD receives the parasitic light over free space and is configured as a dichroic filter inducing losses to the light at the parasitic wavelength.

Abstract: A laser system, comprised of: a laser cavity; a gain medium a pump, a saturable absorber (SA); a first mirror and a second mirror; wherein a ratio of an area of the beam area within the SA to an area of the laser beam within the gain medium is greater than 1, and wherein the beam generates a gain medium radius spot on the gain medium and a saturable absorber radius spot on the saturable absorber such that a ratio between a saturable absorber radius spot on the saturable absorber and the gain medium radius spot on the gain medium is within a range of 1.7-7 is disclosed. A method for using the laser system e.g., for producing a pulsed energy is further disclosed.

Abstract: In example implementations of a vertical-cavity surface-emitting laser (VCSEL), the VCSEL includes a p-type distributed Bragg reflector (p-DBR) layer and a p-type ohmic (p-ohmic) contact layer adjacent to the p-DBR layer. The p-DBR layer may include an oxide aperture and the p-ohmic contact layer may have an opening that is aligned with the oxide aperture. The opening may be filled with a dielectric material. A metal layer may be coupled to the p-ohmic contact layer and encapsulate the dielectric material.

Abstract: A method for generating a single-cavity dualcomb or multicomb for laser spectroscopy, the method comprising the steps of providing a laser system comprising a pump source, a gain medium, and a resonator having a spectral filter; spectrally filtering, by the spectral filter, light in the resonator and attenuating, in particular blocking, by the spectral filter, one or more wavelength bands at least one of which being located completely within the gain bandwidth of the laser system such that two or more at least partially separated spectral regions are provided; mode-locking the two or more at least partially separated spectral regions.

Abstract: A plasmonic quantum well laser may be provided. The plasmonic quantum well laser includes a plasmonic waveguide and a p-n junction structure extends orthogonally to a direction of plasmon propagation along the plasmonic waveguide. Thereby, the p-n junction is positioned atop a dielectric material having a lower refractive index than material building the p-n junction, and the quantum well laser is electrically actuated. A method for building the plasmonic quantum well laser is also provided.

Abstract: A method for fabricating an ellipsoidal or semi-ellipsoidal semiconductor structure includes steps of providing a semiconductor substrate and fabricating an ellipsoidal or semi-ellipsoidal cavity structure on the semiconductor substrate. The cavity structure encompasses a seed surface of the semiconductor substrate. The method includes a further step of growing the ellipsoidal or semi-ellipsoidal semiconductor structure within the ellipsoidal or semi-ellipsoidal cavity structure from the seed surface of the semiconductor substrate. Fabricating the cavity structure includes arranging a droplet comprising a sacrificial material on the semiconductor substrate, forming a layer of a coating material on the semiconductor substrate and the droplet, and selectively removing the sacrificial material of the droplet to expose the cavity structure.

Abstract: A multi-frequency laser system comprises a master oscillator to generate a master beam and an arm splitter to split the master beam into a first beam and a second beam. The first beam is provided to a primary mode arm for generation of a primary mode beam and the second beam is provided to a sideband mode arm for generation of a sideband mode beam. The sideband beam arm comprises a modulator to modulate the second beam to generate a beam comprising sidebands; a filter to select a particular sideband mode from the beam comprising sidebands; an amplifier cavity to amplify the particular sideband mode and suppress other residual modes; and an acousto-optical modulator to shift the frequency of each mode of an amplified selected sideband beam to generate a sideband mode beam. The primary and sideband mode beams are provided in a coordinated manner to enact a quantum gate.

Abstract: A frequency electromagnetic radiation generation system including: a non linear crystal producing THz frequency electromagnetic radiation; a fundamental beam that interacts with the non linear crystal thereby emitting a THz frequency electromagnetic radiation emission; a silicon intermediary coupled to the non linear crystal for output channeling the THz frequency electromagnetic radiation emission to an output environment; the system utilising a fundamental beam which has a photon energy below the bandgap energy of silicon.

Abstract: A light source comprises a GeSn active zone inserted between two contact zones. The active zone is formed directly on a silicon oxide layer by a first lateral epitaxial growth of a Ge germination layer followed by a second lateral epitaxial growth of a GeSn base layer. A cavity is formed between the contact zones by encapsulation and etching, so as to guide these lateral growths. A vertical growth of GeSn is then achieved from the base layer to form a structural layer. The active zone is formed in the stack of base and structural layers.

Abstract: A distributed feedback (DFB) laser outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The DFB laser includes a separate confinement heterostructure layer positioned between the quantum well active layer and then-type cladding layer. The DFB laser includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and then-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The DFB laser has a function to select a specific wavelength by returning a specific wavelength in the wavelength-variable laser.

Abstract: A vertical cavity surface emitting laser includes: an active layer including a quantum well structure including one or more well layers including a III-V compound semiconductor containing indium as a group III constituent element; an upper laminated region containing a carbon dopant; and a substrate for mounting a post including the active layer and the upper laminated region, in which the active layer is provided between the upper laminated region and the substrate, the quantum well structure has a carbon concentration of 2×1016 cm?3 or less, and the upper laminated region includes a pile-up layer of indium at a position away from the active layer.

Abstract: It is provided a method for fabricating an electroabsorption modulated laser comprising generating a single mode laser section and an electroabsorption modulator section, comprising fabricating at least one n-doped layer of the laser section and at least one n-doped layer of the modulator section; generating an isolating section for electrically isolating at least the n-doped layer of the laser section and the n-doped layer of the modulator section from one another. Generating the isolating section comprises epitaxially growing at least one isolating layer and structuring the isolating layer before the generation of the n-doped layer of the laser section and the n-doped layer of the modulator section.

Abstract: A heat exchanger configured to cool an energy output device, and systems, devices, and methods thereof, can comprise a heat exchanger housing and an internal chamber defined in the housing that is configured to be filled with a phase-change material (PCM). The internal chamber can be provided at a first predetermined level inside the housing relative to the top surface of the housing and can extend under a first predetermined portion of the top surface of the housing. The internal chamber can include a plurality of PCM channels configured to be filled with the PCM and to accommodate phase changes of the PCM in multiple phase-change directions. Optionally, the plurality of PCM channels can be defined by a plurality of fins and/or the internal chamber can be accessible to outside the housing via at least one PCM interface configured to receive and pass therethrough the PCM.

Abstract: A line narrowing module includes a prism that refracts laser light in a first plane, a grating that disperses the laser light in the first plane, first to fourth elements, and a rotation mechanism and narrows the linewidth of the laser light. The second element is supported between the first and fourth elements by the first element. The rotation mechanism rotates the second element relative to the first element around an axis intersecting the first plane. The prism is located between the second and fourth elements and so supported by the second element that the rotation mechanism rotates the prism and the second element. The third element has elasticity and is compressed and located between the prism and the fourth element. The fourth element receives reaction force from the compressed third element. The second element is mechanically independent of the fourth element in the rotational direction of the rotation mechanism.

Abstract: Techniques and circuitry for a semiconductor laser with enhanced lasing wavelengths stabilization are described. A semiconductor laser can generate an optical signal (e.g., single or multi-wavelength), for use in a Dense Wavelength Division Multiplexing (DWDM) interconnect system. The stabilization circuitry can include temperature sensor circuitry that measures an operational temperature of the semiconductor laser, and a feedback controller that can determine a temperature-induced wavelength shift that may be experienced by the multi-wavelength optical signal based on the laser's temperature. The feedback controller is also configured to generate a compensation signal that is determined to cause a complimentary shift in the multi-wavelength optical signal, where the complimentary shift can compensate for the temperature-induced wavelength shift.

Abstract: A laser device for laser resonance ionization includes a wavelength variable grating-type titanium-doped sapphire laser and includes a titanium (Ti) doped titanium sapphire crystal disposed within a resonator. The titanium sapphire crystal is fixedly disposed on a stage. The titanium-doped sapphire crystal can be moved in the optical axis direction by the stage, thereby changing the position of the titanium-doped sapphire crystal. The switching between the wideband mode and the high-output mode can be performed by changing the position of the titanium-doped sapphire crystal.

Abstract: An aspect of a photon source may have a substrate with a surface, a focus lens disposed above the surface, and a plurality of optical sources. Each optical source may be composed of a mirror and an optical emitter. The optical emitter may include a beam twister. The emitter is aligned with the mirror along an axis and may emit a collimated beam along the axis, A plurality of mirrors may be composed of each mirror of the plurality of optical sources, arranged in a first ring-like configuration. Alternatively, the plurality of mirrors may be aggregated into a polygonal pyramidal mirror. A plurality of emitters may be composed of each emitter of the plurality of optical sources, arranged in a second ring-like configuration. The optical emitters may be composed of a laser diode mounted on a sub-mount having a plane orthogonal to the planar surface.

Abstract: Improve semiconductor device performance. The wiring WL1A on which the semiconductor chip CHP1 in which the semiconductor lasers LD is formed is mounted has a stub STB2 in the vicinity of the mounting area of the semiconductor chip CHP1.