Abstract: A multi-core optical amplifying fiber device includes a plurality of multi-core optical amplifying fibers including a plurality of core portions doped with amplification medium and a cladding portion formed at outer peripheries of the plurality of core portions; and a connection portion connecting the core portions of the plurality of multi-core optical amplifying fibers to one another. The connection portion connects the core portions to restrain deviation, between every connected core portions, of amplification gain for a total length of the core portions connected one another.

Abstract: A fiber-based optical amplifier is assembled in a compact configuration by utilizing a flexible substrate to support the amplifying fiber as flat coils that are “spun” onto the substrate. The supporting structure for the amplifying fiber is configured to define the minimal acceptable bend radius for the fiber, as well as the maximum diameter that fits within the overall dimensions of the amplifier package. A pressure-sensitive adhesive coating is applied to the flexible substrate to hold the fiber in place. By using a flexible material with an acceptable insulative quality (such as a polyimide), further compactness in the final assembly is achieved by locating the electronics in a space underneath the fiber enclosure.

Abstract: An optical image amplifier device capable of amplifying low-intensity backscattered illumination includes an optical port having an input, an output, and a controller having an ON state and an OFF state, the controller connecting the input and the output to form an optical loop in the ON state and disconnecting the input and the output in the OFF state, and an optical relay housing the optical loop and connected to the optical port having a gain medium configured for amplifying a signal beam propagating inside the optical loop in the ON state.

Abstract: Embodiments include a gain system and method. The system includes a gain medium with a plurality of plasmonic apparatus. Each plasmonic apparatus includes a substrate having a first plasmonic surface, a plasmonic nanoparticle having a second plasmonic surface, and a dielectric-filled gap between the first plasmonic surface and the second plasmonic surface. A plasmonic cavity is created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and has a first fundamental wavelength ?1 and second fundamental wavelength ?2. Fluorescent particles are located in the dielectric-filled gap. Each fluorescent particle has an absorption spectrum at the first fundamental wavelength ?1 and an emission spectrum at the second fundamental wavelength ?2. An excitation applied to the gain medium at the first fundamental wavelength ?1 produces an amplified electromagnetic wave emission at the second resonant wavelength ?2.

Abstract: A laser device includes an apparatus for producing amplified laser pulses, using a plurality of amplifying optical fibers, and groups the basic amplified pulses into an overall amplified pulse, as well as a target, onto which the overall amplified pulse is directed such as to generate a predetermined physical process thereon, which causes a change of state in the target. The laser device is configured to measure at least one distinctive parameter of the generated physical process; adjust at least one characteristic for adjusting the basic amplified laser pulses; and analyze a plurality of measurements for different adjustments. The device analyzes the measurements many times in loops for different laser pulse adjustment characteristics, enabling an optimization by a heuristic method. Also provided is a heuristic optimization method implemented by the laser device.

Abstract: An apparatus includes a curved multimode polymer waveguide having at least one inflection point and a doped region being doped with an amplifying dopant. An optical pump source or electrical pump source is configured to excite the doped region and amplify the optical signal transmitting along the curved multimode polymer waveguide.

Abstract: An apparatus comprising a case, an optical amplifier, and an optical transceiver is provided. The optical amplifier and the optical transceiver are included in the case. The case includes a top portion and a bottom portion. The top portion includes first to third sections arranged in a direction perpendicular to a direction extending from the top portion to the bottom portion. The first section has a larger area than the third section and the second section divides the first and third sections. The third section includes a first cavity including at least one portion of the optical amplifier. The optical amplifier is provided using at least one of an amplifying fiber, a pumping light source, an isolator, a wavelength-division multiplexer (WDM) coupler, a wavelength-variable optical filter, a monitoring-tap photo diode, and a driving control unit.

Abstract: An optical fiber for amplification includes a core having an inner core and an outer core surrounding the outer circumferential surface of the inner core. The relative refractive index difference of the inner core to a cladding is smaller than the relative refractive index difference of the outer core to the cladding. The outer core is entirely doped with erbium. The theoretical cutoff wavelength of an LP11 mode light beam is a wavelength of 1,565 nm or more. The theoretical cutoff wavelength of an LP21 mode light beam is a wavelength of 1,530 nm or less. The theoretical cutoff wavelength of the LP02 mode light beam is a wavelength of 980 nm or less.

Abstract: A bundle structure is obtained by arranging optical fibers having equal diameters in a close-packed arrangement around the outer circumference of a center optical fiber. The optical fibers are signal light optical fibers that transmit signal lights. The optical fiber is a pump light optical fiber that transmits pump light. The number of optical fibers is equal to the number of cores in the multi-core fiber. The bundle structure and the multi-core fiber are connected to one another by adhering or fusing. The cores and the cores are optically connected, and the core and the cladding are optically connected. When connecting, the mode field diameter of the cores and the cores are substantially equivalent. In addition, the outer diameter (diameter of circumscribed circle including optical fibers) of the bundle structure is set so as not to be greater than the outer diameter of the multi-core fiber.

Abstract: A new monolithic resonator metasurface design achieves ultra-high Q-factors while using only one resonator per unit cell. The metasurface relies on breaking the symmetry of otherwise highly symmetric resonators to induce intra-resonator mixing of bright and dark modes (rather than inter-resonator couplings), and is scalable from the near-infrared to radio frequencies and can be easily implemented in dielectric materials. The resulting high-quality-factor Fano metasurface can be used in many sensing, spectral filtering, and modulation applications.

Abstract: There is provided a slab amplifier including an optical system (48, 51) provided in a chamber (47) to allow a seed beam having entered from a first window into the space between a pair of electrodes (42, 43) to be repeatedly reflected between the space so that the seed beam is amplified to be an amplified beam; a first aperture plate (61) provided between the first window and the electrodes, and having an opening of a dimension equal to or greater than a cross-section of the seed beam and equal to or smaller than a dimension of the first window; and a second aperture plate (62) provided between the second window and the electrodes, and having an opening of a dimension equal to or greater than a cross-section of the amplified beam and equal to or smaller than a dimension of the second window.

Abstract: Devices and methods for lessening a thermal dependence of gain profile of an optical amplifier are disclosed. An optical beam is split in a plurality of sub-beams with a thermally variable power splitting ratio, e.g. one sub-beam may travel a longer optical path length than another. When the sub-beams are recombined, they interfere with each other, causing the throughput to be wavelength dependent. An amplitude of this wavelength dependence is thermally variable due to the thermally variable power splitting ratio. The thermally variable power splitting ratio and the optical path length difference are selected so as to offset a thermal variation of a spectral gain profile of an optical amplifier.

Abstract: An optical amplification device includes: a semiconductor optical amplifier; a first detector that detects an input optical power of the semiconductor optical amplifier; a second detector that detects an output optical power of the semiconductor optical amplifier; and a controller that controls a driving current of the semiconductor optical amplifier, wherein the controller supplies a predetermined driving current to the semiconductor optical amplifier when an optical signal is not input to the semiconductor optical amplifier, the second detector detects an optical power of Amplified Spontaneous Emission (ASE) output from the semiconductor optical amplifier when the predetermined driving current is supplied to the semiconductor optical amplifier, and the controller controls the driving current of the semiconductor optical amplifier based on the input optical power of the semiconductor optical amplifier detected by the first detector, and the optical power of the ASE.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for optical communications. One optical amplifier includes an input port; a bar-cross switch optically coupled to the input port; a first gain stage optically coupled between first port of the bar-cross switch and to an output port; and a secondary gain stage optically coupled between a second port and a third port of the bar-cross switch, wherein in a bar-state of the bar-cross switch the secondary gain stage is bypassed and in a cross-state, the secondary gain stage and the first gain stage are applied to an input light beam.

Abstract: An amplification optical fiber operable to propagate light beams in a plurality of modes in a predetermined wavelength range through a core doped with a rare earth element, wherein Expression (1) is satisfied, where a cutoff wavelength of a propagated highest mode light beam is defined as ?max, under conditions in which the cutoff wavelength of the highest mode light beam is defined as ?c, a shortest wavelength of the wavelength range is defined as ?min, and a cutoff wavelength of a second-highest mode light beam to the highest mode light beam is ?min. ?c>0.5 ?min+0.5 ?max??(1).

Abstract: Embodiments include a gain system and method. The system includes a gain medium with a plurality of plasmonic apparatus. Each plasmonic apparatus includes a substrate having a first plasmonic surface, a plasmonic nanoparticle having a second plasmonic surface, and a dielectric-filled gap between the first plasmonic surface and the second plasmonic surface. A plasmonic cavity is created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and has a first fundamental wavelength ?1 and second fundamental wavelength ?2. Fluorescent particles are located in the dielectric-filled gap. Each fluorescent particle has an absorption spectrum at the first fundamental wavelength ?1 and an emission spectrum at the second fundamental wavelength ?2. An excitation applied to the gain medium at the first fundamental wavelength ?1 produces an amplified electromagnetic wave emission at the second resonant wavelength ?2.

Abstract: A broadband emission material according to the present invention includes: a fluoride glass containing 20 to 45 mol % of AlF3, 25 to 63 mol % of alkaline-earth fluorides in total and 3 to 25 mol % of at least one fluoride of element selected from the group consisting of Y, La, Gd and Lu; and ytterbium ions incorporated in the fluoride glass as divalent rare-earth ions so as to serve as a luminescent center, wherein the fluoride glass includes 1 to 15 mol % of at least one halide of element selected from the group consisting of Al, Ba, Sr, Ca and Mg and element selected from the group consisting of Cl, Br and I; and wherein the alkaline-earth fluorides includes 0 to 15 mol % of MgF2, 7 to 25 mol % of CaF2, 0 to 22 mol % of SrF2 and 0 to 5 mol % of BaF2.

Abstract: A multiple-output laser component is described with a plurality of diode lasers in a common package, each of the diode lasers having distinct electrical control and optically coupled to a distinct output fiber, the component configured such that up to a maximum total output power can be selectively and dynamically partitioned among said diode lasers. The dynamic allocation can be based on demand for laser power in a fiber optic coupled to each diode laser. The multi-output laser component can be used to drive amplifiers associated with a multicast switch in some embodiments.

Abstract: According to one aspect, the invention relates to a device comprising an optical fiber having a high Brillouin threshold, said device including an optical fiber (101) suitable for propagating a high-power optical signal beam, means (11) for coupling a signal beam to an entrance end of the optical fiber (101) and a tubular structure (10) comprising at least one first tube (103) and at least one first adhesive material (102). According to the present description, at least one portion of the optical fiber is immobilized in the tubular structure (10) by means of the first adhesive material (102), which adheres both to the internal surface of the first tube (103) and to the external surface of the optical fiber (101).

Abstract: A distributed Raman amplifier system is disclosed. Distributed Raman amplifier systems can include a spool of fiber disposed between a distributed Raman amplifier and local or proximate optical point-loss sources, a carrier hotel for example. The spool of fiber has a fiber of sufficient length to offset aggregated losses, which prevents the distributed Raman amplifier from shutting down while also allowing the distributed Raman amplifier to achieve entitled gain by pumping the fiber in the spool.