An optical amplification device includes: a polarization demultiplexing unit that separates an optical signal into a first polarized wave and a second polarized wave; a first optical amplification unit that amplifies the first polarized wave by using a first amplification medium; a second optical amplification unit that amplifies the second polarized wave by using a second amplification medium; a first band demultiplexing unit that demultiplexes the first polarized wave into a band component of the first polarized wave and a band component of first phase conjugate light; a second band demultiplexing unit that demultiplexes the second polarized wave into a band component of the second polarized wave and a band component of second phase conjugate light; a signal monitoring unit that measures a first optical power value of either the band component of the first polarized wave or the band component of the first phase conjugate light and a second optical power value of either the band component of the second polarized wave or the band component of the second phase conjugate light; an amplification gain control unit that controls an amplification band and gain of the first amplification medium and an amplification band and gain of the second amplification medium on the basis of the first optical power value and the second optical power value; and a polarization combination unit that multiplexes the band component of the first polarized wave and the band component of the second polarized wave not measured by the signal monitoring unit.

A metasurface includes a plurality of Bragg mirrors, each having a defect cavity therein, arrayed in a grid. A heat source is provided for each of the plurality of Bragg mirrors. Each heat source is positioned to selectively modulate heat applied to its respective Bragg mirror and to impart a different phase shift via the applied heat from the heat source.

Some embodiments are directed to a generating device, including a pulse laser source providing primary photons having at least one wavelength, shaping device(s) acting on the primary photons to provide an input beam, a nonlinear crystal, and controller(s) generating, in the nonlinear crystal, at least one electric field that is synchronous with the input beam and suitable for inducing a phase mismatching in the nonlinear crystal through an electro-optical effect, in order to convert the primary photons of the input beam into secondary photons having wavelengths belonging to a supercontinuum.

A high-average-power OPCPA amplifier comprising a pump laser, a signal laser, and a nonlinear crystal amplifier. The pump laser includes an Nd:YVO.sub.4 laser oscillator-regenerative amplifier, an Nd:YAG boost amplifier, a frequency-doubling convertor, and a frequency-tripling convertor. The signal laser includes a supercontinuum generator, a pulse stretcher, and a pulse compressor. The chirped signal and the pump laser is intersected with a noncollinear angle of 3.0 to 4.0 in the nonlinear crystal amplifier and the temperature of the crystal amplifier is set at higher than 320K for simultaneous temperature- and wavelength-insensitive phase-matching.

A system is provided for generating a laser beam via non-linear effects, including: a monofrequency continuous-wave laser source; and an external resonant cavity referred to as a microchip cavity. The microchip cavity is composite insofar as it is a unitary assembly of a plurality of materials g: at least one nonlinear crystal; an entrance mirror; a concave mirror deposited on a material fixed to the nonlinear crystalthe material on which the concave mirror is deposited is different from the constituent material of the nonlinear crystal; a first thermoelectric module for controlling the temperature of the nonlinear crystal; and at least one second thermoelectric module for controlling at least the temperature of the material on which the concave mirror is deposited.

Tunable monolithic cavity-based frequency converter pumped by a single-frequency laser where cavity resonance(s) are achieved by independently changing the temperatures of different sections of the crystal, including the periodically poled section and one or more adjacent, non-poled regions. Having independent control of the phase matching temperature and the cavity resonance for a down-converted beam increases the efficiency.

A wavelength converter stabilizes output light intensity in which the light coupling efficiency to a light waveguide core is not easily varied. A mounting structure is adopted in which a substrate of a wavelength conversion element is a material with a lower refractive index for signal light than that of the core, and a support structure that suppresses elastic deformation by supporting the element through a contact at a tip end surface at a position corresponding to both end portions of the core at the occurrence of elastic deformation due to the thermal stress of the element is provided. The support structure is provided at a portion apart from a temperature control element at the top surface of a metal housing bottom surface member, and its top surface is disposed in the vicinity of a portion corresponding to both end portions of the core of the element in a support member.

An optimized wavelength-tuned nonlinear frequency conversion process using a liquid crystal clad waveguide. The process includes implanting ions on a top surface of a lithium niobate crystal to form an ion implanted lithium niobate layer. The process also includes utilizing a tunable refractive index of a liquid crystal to rapidly change an effective index of the lithium niobate crystal.

Tunable monolithic cavity-based frequency converter pumped by a single-frequency laser where cavity resonance(s) are achieved by independently changing the temperatures of different sections of the crystal, including the periodically poled section and one or more adjacent, non-poled regions. Having independent control of the phase matching temperature and the cavity resonance for a down-converted beam increases the efficiency.

An OPO with very fast and accurate tuning. The angle of the crystals in the OPO is controlled by converting the linear motion of a voice coil into rotational motion. In preferred embodiments one or two OPO crystals are mounted as a crystal unit that can rotate around an axis such that the angle of the crystals with respect to the beams' direction can be varied to generate the desired wavelengths. The crystal unit has a lever that is connected to the shaft of the voice coil such that as the shaft extend or retracts the level is pulled or pushed and the linear motion of the shaft is converted to an angular motion of the crystal unit. The position of the voice-coil shaft is controlled in a close-loop based on a built-in encoder. The relation between the reading of the encoder and the crystals' angle is recorded and provides the calibration of the unit. Preferably calibration is done by measuring the output wavelength of the OPO as a function of the encoder position.