Abstract: An optical parametric amplifier and methods for idler extraction therein. Certain examples provide a method of extracting the idler at intermediate points within the optical parametric amplifier chain to improve conversion efficiency and/or maintain high beam quality (high Strehl ratio), where the pump beam has non-uniform profile. In one example, optical parametric amplifier includes an amplifier chain having a plurality of gain stages, each gain stage including a non-linear optical crystal, the plurality of gain stages configured to receive a signal seed and a pump beam and to produce an idler and an amplified signal, the pump beam having a non-uniform spatial profile, and a plurality of idler extractors interspersed with the plurality of gain stages and configured to extract the idler from intermediate points within the amplifier chain. The idler extractors can include polarizers, beam displacer crystals, or dichroic mirrors, for example.

Abstract: A non-linear optical device is provided. The device comprises an optical disk or ring microresonator fabricated from a material that exhibits an optical nonlinearity able to produce degenerate four-wave mixing (FWM) in response to a pump beam having a pump frequency in a specified effective range. The microresonator is conformed to exhibit an angular group velocity minimum at a pump frequency within the specified effective range such that there is zero angular group velocity dispersion at the pump frequency. We refer to such a pump frequency as the “zero dispersion frequency”. In embodiments, excitation of the resonator by a pump beam of sufficient intensity at the zero-dispersion frequency causes the resonator to emit a frequency comb of entangled photon pairs wherein the respective frequencies in each pair are symmetrically placed about the zero-dispersion frequency.

Abstract: Method and device for the optical parametric chirped pulse amplification, using two pump signals and making it possible to extend the spectral gain band. According to the invention, which is particularly applicable to laser-matter interaction, a four-wave mixing effect is used, preferably in an optical fiber (F), between each pulse (S) and the two pump signals (P1, P2); and the half-sum (fM) of the respective optical frequencies (fP1, fP2) of these signals pertains to the pulse spectrum support.

Abstract: Disclosed herein are a system and corresponding method for sensing terahertz radiation. The system collects terahertz radiation scattered from a target and upconverts the collected radiation to optical frequencies. A frequency-domain spectrometer senses spectral components of the upconverted signal in parallel to produce a spectroscopic measurement of the entire band of interest in a single shot. Because the sensing system can do single-shot measurements, it can sense moving targets, unlike sensing systems that use serial detection, which can only be used to sense stationary objects. As a result, the sensing systems and methods disclosed herein may be used for real-time imaging, including detection of concealed weapons, medical imaging, and hyperspectral imaging.

Abstract: Embodied is a two-color, fiber-delivered picosecond source for coherent Raman scattering (CRS) imaging. A wavelength tunable picosecond pump is generated by nonlinear spectral compression of a prechirped femtosecond pulse from a mode-locked titanium:sapphire (Ti:S) laser. A 1064-nm picosecond Stokes pulse is generated by an all-fiber time-lens source (or suitable alternative source) that is synchronized to the Ti:S laser. The pump and Stokes beams are combined in an optical fiber coupler, which serves not only as the delivery fiber but also as the nonlinear medium for spectral compression of the femtosecond pulse. CRS imaging of mouse skin is performed to demonstrate the practicality of this source.

Abstract: Pulses from a mode-locked Yb-doped laser (12) are spectrally broadened in an optical fiber (28), and temporally compressed in a grating compressor (32), then frequency-doubled (34) and used to pump an optical parametric oscillator (OPO) (40). The OPO output is tunable over a wavelength range from about 600 nm to about 1100 nm. Mode-locking in the Yb-doped laser (12) is accomplished with a SESAM (14) or by Kerr-lens mode-locking with a Kerr medium (82) and a hard aperture (84).

Abstract: An Optical Parametric Oscillator (OPO) that includes optical elements located and oriented to form a non-planer, image-rotating ring cavity. To provide a high quality well shaped output beam, the OPO comprises a plurality of reflecting surfaces, designed to rotate the resonating beam by 90 degrees for each round trip in the cavity. Preferred embodiments include a first non-linear crystals and a similar second non-linear crystal mounted side-by-side on a single rotating stage. To minimize the adverse effects of walk-off, reflecting unit is positioned to cause the output of the first crystal to be reflected into the second crystal. The two crystals are aligned so as to cause walk-off in the first of the two crystals to be cancelled by opposite walk-off in the second crystal.

Abstract: Techniques and structure are disclosed for implementing a spatial walk-off compensation mechanism having an integral tilt function. In some embodiments, the mechanism may comprise a tilt-ball mount having an integrated walk-off compensation medium. In some embodiments, the mechanism may be configured to receive an output beam from a non-linear converter (e.g., optical parametric oscillator or OPO) implementing a non-linear medium comprising a bi-refringent material (e.g., zinc germanium phosphide, or ZnGeP2; cadmium silicon phosphide, or CdSiP2). In some embodiments, the walk-off compensation medium may comprise the same material and/or have the same cut as the non-linear medium. In some embodiments, the mechanism may he manually and/or mechanically adjusted/repositioned to reduce beam walk-off and/or to more precisely direct the beam. In some embodiments, the mechanism may be implemented in mid-infrared (MIR) applications. Numerous configurations and variations will he apparent in light of this disclosure.

Abstract: A fundamental wavelength light generating unit generates light of a fundamental wavelength in accordance with an output wavelength instruction signal. An optical amplifier unit amplifies the light of the fundamental wavelength. A wavelength converting part includes nonlinear optical crystals that each perform wavelength conversion and temperature regulators that each regulate the temperature of the corresponding nonlinear optical crystal, wherein the wavelength converting part converts the light amplified by the optical amplifier unit to light of the wavelength indicated by the output wavelength instruction signal. A storage unit stores correspondence information that indicates a correspondence relationship between the wavelength of the output light and the temperature of each of the nonlinear optical crystals based on the corresponding wavelength.

Abstract: Systems and methods for producing high-energy, pico-second laser pulses are disclosed. Systems and methods include using a modelocked laser source to drive an OPO (optical parametric oscillator) and an OPA (optical parametric amplifier) such that the OPA and OPO self-synchronize without the use of separate synchronization components and produce high-energy output without requiring pulse stretchers or pulse compressors, making the laser system viable for portability and vehicle mounting from both cost and durability standpoints.

Abstract: The invention relates to an apparatus for generation of electromagnetic radiation, having a pump light source that emits an excitation radiation at a first wavelength, and having an optical waveguide that generates frequency-converted radiation at a second and a third wavelength, by means of degenerate wave mixing, from the excitation radiation of the pump light source.

Abstract: This disclosure provides a second harmonic generator and an optical parametric oscillator, the second harmonic generator and the optical parametric oscillator comprise one or more nonlinear optical frequency conversion crystal and a pump laser source, the nonlinear optical frequency conversion crystal is a monoclinic Ga2S3 crystal, the space group of the monoclinic Ga2S3 crystal is Cc, and the unit cell parameters are a=11.1 ?, b=6.4 ?, c=7.0 ?, ?=90°, ?=121°, ?=90°, and Z=4.

Abstract: Techniques and structure are disclosed for implementing a spatial walk-off compensation mechanism having an integral tilt function. In some embodiments, the mechanism may comprise a tilt-ball mount having an integrated walk-off compensation medium. In some embodiments, the mechanism may be configured to receive an output beam from a non-linear converter (e.g., optical parametric oscillator or OPO) implementing a non-linear medium comprising a bi-refringent material (e.g., zinc germanium phosphide, or ZnGeP2; cadmium silicon phosphide, or CdSiP2). In some embodiments, the walk-off compensation medium may comprise the same material and/or have the same cut as the non-linear medium. In some embodiments, the mechanism may be manually and/or mechanically adjusted/repositioned to reduce beam walk-off and/or to more precisely direct the beam. In some embodiments, the mechanism may be implemented in mid-infrared (MIR) applications. Numerous configurations and variations will be apparent in light of this disclosure.

Abstract: In a quantum entangled photon pair generator selectively generating polarization entangled photon pairs and time-bin entangled photon pairs, an excitation optical pulse shaper receives a linearly polarized optical pulse, and selectively outputs either one of a polarization excitation optical pulse pair to be a seedlight pulse for a polarization entangled photon pair and a consecutive excitation optical pulse pair to be a seedlight pulse for a time-bin entangled photon pair. An optical interferometer receives the polarization excitation optical pulse pair or the consecutive excitation optical pulse pair, and outputs a correlated photon pair forming signal and idler photons through a parametric fluorescence process. A quantum entangled photon pair extractor spatially extracting wavelength components corresponding to photons of the quantum entangled photon pair to output the components as the polarization entangled photon pair or the time-bin entangled photon pair.

Abstract: A method for amplifying optical signals includes determining a source optical signal, generating a first resultant signal including a pump signal and the source optical signal, sending the first resultant signal through a non-linear element to generate a second resultant signal including the first resultant signal and an idler signal, and sending the second resultant signal through a non-linear element to perform phase-sensitive amplification. The phase-sensitive amplification results in a third resultant signal including an amplified source optical signal, the pump signal, and the idler signal. The method also includes filtering the third resultant signal to remove the pump signal and the idler signal and outputting the amplified source optical signal.

Abstract: A monolithic fixed optical delay generator includes an optical substrate having a front face and a back face. A front coating is on the front face and a back coating is on the back face. The front coating is (i) highly reflective to a first wavelength and highly transmissive to a second wavelength while the back coating is highly reflective to the second wavelength, or (ii) the front coating is highly reflective to the second wavelength and is highly transmissive to the first wavelength while the back coating is highly reflective to the first wavelength.

Abstract: A pulsed laser system may include a Raman fiber that is configured to act as multiple wavelength Raman laser. The fiber is configured to receive a pulsed input beam from an input source and convert the input beam to an output beam having narrow band outputs at first and second frequencies v1 and v2.

Abstract: Provided is a nonlinear optical device manufactured with 4H silicon carbide crystal. The nonlinear optical crystal may be configured to alter at least a light beam (12) at a frequency to generate at least a light beam (16) at a further frequency different from the frequency. The nonlinear optical crystal comprises a 4H silicon carbide crystal (13). The nonlinear optical device is more compatible with practical applications in terms of outputting mid-infrared laser at high power and high quality and thus are more applicable in practice, because the 4H silicon carbide crystal has a relatively high laser induced damage threshold, a relatively broad transmissive band (0.38-5.9 ?m and 6.6-7.08 ?m), a relatively great 2nd-order nonlinear optical coefficient (d15=6.7 pm/V), a relatively great birefringence, a high thermal conductivity (490 Wm?1K?1), and a high chemical stability.

Abstract: An OPO is disclosed capable of rapid frequency tuning by non-mechanical means. The OPO includes a resonant cavity including one or more non-linear crystals in an optical path thereof. A pump laser pulse is transmitted into the resonant cavity simultaneously with a seed beam having a desired wavelength. The output beam from the resonant cavity has the same center wavelength as the seed beam. The wavelength of the seed beam may be modulated at a frequency larger than the pulse rate of the pump laser or larger than the inverse of the pulse duration. The OPO disclosed may be used to perform DIAL analysis wherein intra-pulse modulation of an output beam is used to obtain measurements of absorption at multiple frequencies for each pulse of a pump beam.

Abstract: Improved production of entangled photon pairs (biphotons) via spontaneous parametric down conversion (SPDC) is provided. In one aspect, forward-wave SPDC is performed in a monolithic resonator (resonant for both signal and idler) having a double pass pump geometry to provide a spectrally bright source of biphotons. In another aspect, backward-wave SPDC is performed in a resonator (resonant for both signal and idler) to provide a spectrally bright source of biphotons. For either of these approaches, the biphotons can be made to have polarization entanglement by using quasi phasematching (QPM) with two QPM periods simultaneously.

Abstract: A method of generating light is disclosed. The method comprises: directing an optical pulse to a semiconductor optical amplifier being at a temperature above 0° C. The optical pulse is preferably characterized by a wavelength within an emission spectrum of the semiconductor optical amplifier and by a pulse area selected to induce Rabi oscillations in the semiconductor optical amplifier, and to emit light at a frequency of at least 1 THz.

Abstract: A quantum entangled photon pair generating device, an optical frequency dividing filter, a 2N-input/2N-output optical switch, a 2N number of quantum key receiving devices, an optical transmission path and a control unit are provided. The quantum entangled photon pair generating device generates quantum entangled photon pairs. The optical frequency dividing filter receives the quantum entangled photon pairs, divides an optical frequency region by 2N, and performs output. The 2N-input/2N-output optical switch allocates photons of the 2N number of optical frequency regions to any one of a 2N number of output ports, and outputs the photons.

Abstract: Tunable light sources having a single optical parametric generation (OPG) source that results in an amplified, narrow bandwidth seed beam and methods of tuning therewith are disclosed. The tunable light source may include a polarization rotator to rotate a pump beam before a first pass through an OPG, and a linear-to-circular polarization device to polarize the pump beam directed back toward the OPG for a second pass therethrough. Alternately, the tunable light source may include an OPG source through which a pump beam passes only in the first direction, a separator that separates a signal beam from the pump beam exiting from the OPG, a narrowband wavelength filter that receives the signal beam and generate a seed beam, and a reflecting surface that directs the seed beam back through the OPG (opposite the first direction) to seed the back part of the pulse of the pulse laser.

Abstract: An optical amplification device includes a first optical amplification portion, an intermediate portion and a second optical amplification portion. The first optical amplification portion receives input light including signal light and pump light, generates idler light as wavelength converted light based on wavelengths of the signal light and the pump light, and outputs first output light including signal light, pump light and idler light. The intermediate portion outputs second output light, and includes a demultiplexing portion that demultiplexes the first output light into signal light, pump light and idler light, a multiplexing portion that generates the second output light by multiplexing signal light, pump light and idler light, and a polarization plane adjustment portion that exchanges mutually orthogonal polarization components of idler light. The second optical amplification portion amplifies an intensity of signal light included in the second output light.

Abstract: A method for wavelength tunable output from a broadband spectrum using a quasi phase-matched optical parametric amplifier/difference frequency generator (CQPM OPA/DFG)-based apparatus involves changing the relative timing of a pump pulse with respect to a seed pulse. The temporal variation varies the location of the spatial/temporal overlap of the spectrally narrow pump pulse over the spectrally broad seed spectrum occurring within the CQPM nonlinear medium. This overlap position determines the portion of the seed pulse that is phase-matched as the signal in the OPA or the seed for DFG. Piezo-electric fiber stretchers may be employed to vary the relative pulse timing and enables tuning of the output from the OPA or DFG without the use of any moving parts. Associated apparatus is disclosed.

Abstract: A coherent light source is provided for producing narrow-linewidth output, continuously tunable within a broad (at least one-octave-wide) range of optical wavelengths. The source is based on type-I or type-0 near-degenerate optical parametric oscillator (OPO), which uses a nonlinear optical crystal with either birefringent phase matching or quasi phase matching. The pump wavelength is chosen such that the OPO degeneracy wavelength (at twice the pump wavelength), is close to the point of zero group-velocity dispersion. That results in an extremely broad OPO bandwidth. Fast OPO wavelength tuning is achieved by rotating an intracavity diffraction grating. In accordance with the invention, the choice of a nonlinear crystal and a pump source determines the overall tuning range. For example, the use of lithium niobate provides tuning over the range of 1.3 to 3 microns, ZGP—3.8 to 8 microns, gallium arsenide—4 to 12 microns, CGA—6 to 13 microns.

Abstract: An optical source 10 comprising an optical output 12, a pump optical source 14, an optical splitter arranged to receive an optical signal from the pump optical source and to split the optical signal into a pump signal and a seed pump signal. A seed signal forming apparatus 18 is arranged to receive the seed pump signal at the pump wavelength and to transform the seed pump signal into a seed signal at a seed wavelength. A first microstructured optical fibre (MSF1) 20 is arranged to receive the pump signal and the seed signal. MSF1 is arranged to cause the pump signal to undergo four-wave mixing seeded by the seed signal on transmission through MSF1 such that a first optical signal at a signal wavelength and second optical signal at an idler wavelength are generated. One of the signal wavelength and the idler wavelength are the seed wavelength and one of the first and second optical signals are provided to the optical output.

Abstract: Method and device for the optical parametric chirped pulse amplification, using two pump signals and making it possible to extend the spectral gain band. According to the invention, which is particularly applicable to laser-matter interaction, a four-wave mixing effect is used, preferably in an optical fibre (F), between each pulse (S) and the two pump signals (P1, P2); and the half-sum (fM) of the respective optical frequencies (fP1, fP2) of these signals pertains to the pulse spectrum support.

Abstract: The present invention relates to an optical parametric oscillator. In particular, the present invention relates to a more optimal rotating image optical parametric oscillator. More specifically, there is described an optical parametric oscillator comprising six mirrored surfaces; wherein two of the mirrored surfaces are provided by a penta prism and the sequence of mirrors is operable to provide a predetermined rotation of a beam passing therethrough.

Abstract: An optical parametric device comprising a slant-stripe periodically poled nonlinear material that is operable to generate signal in response to interaction with a pump wave, the non-linear interaction being such that the pump and idler waves are collinear and the signal wave is non-collinear relative to the pump and idler waves, wherein the slant-stripe non-linear material is able to generate two idler waves and two signal waves, and the device is adapted to allow for the selection and output coupling of a required one of the two signal waves.

Abstract: An intra-cavity optical parametric oscillator. The oscillator includes means for providing a non-linear loss for suppressing relaxation oscillations.

Abstract: Devices and techniques that use nonlinear optical effects in optical fiber to generate optical pulses via nonlinear optical wave mixing for various applications such as coherent Raman microscopic measurements and optical parametric oscillators.

Abstract: A method and an apparatus for processing an optical signal are disclosed wherein an input optical signal having an amplitude profile is combined by means of Bragg scattering with a first pulsed pump signal having a first waveshape and a second pulsed pump signal having a second waveshape. The combined optical signal is input in a nonlinear optical material for frequency converting the input optical signal thereby obtaining an idler signal wherein the first pulsed pump signal co-propagates with the input optical signal and the second pulsed pump signal co-propagates with the idler signal. The idler signal produced has a peak amplitude proportional to the peak amplitude of the input optical signal and a shape corresponding to the second pump waveshape.

Abstract: A method for amplifying optical signals includes determining a source optical signal, generating a first resultant signal including a pump signal and the source optical signal, sending the first resultant signal through a non-linear element to generate a second resultant signal including the first resultant signal and an idler signal, and sending the second resultant signal through a non-linear element to perform phase-sensitive amplification. The phase-sensitive amplification results in a third resultant signal including an amplified source optical signal, the pump signal, and the idler signal. The method also includes filtering the third resultant signal to remove the pump signal and the idler signal and outputting the amplified source optical signal.

Abstract: An optical amplifier amplifies signal light and includes a pump light source that outputs pump light of a wavelength different from that of the signal light; a combining unit that combines the signal light and the pump light output by the pump light source, to output combined light; an amplifying unit that has non-linear optical media that transmit the combined light to amplify the signal light, the amplifying unit further removing, in the non-linear optical media, idler light generated from the signal light and the pump light, and outputting light that results; and an extraction filter that extracts the signal light from the light output by the amplifying unit.

Abstract: A method of despeckling light that includes mixing high-speckle far-red laser light with low-speckle green laser light in amounts selected to achieve a desired color point in a digital image. The far-red laser light may be red laser diodes with wavelengths in the range of 640 to 680 nm. The green laser light may include stimulated-Raman-scattering light from an optical fiber. The desired color point may be DCI red or Rec. 709 red.

Abstract: An optical system and method that use a pump laser, an optical parametric oscillator, and two second harmonic generators to generate three colors of laser light. A recirculating optical sub-system includes a gain-guided optical parametric oscillator and one of the second harmonic generators and has four lenses that form two collimated optical beams between the optical parametric oscillator and the second harmonic generator.

Abstract: A terahertz continuous wave generator includes: an optical intensity modulator configured to modulate an optical signal into DSB optical signals; a local oscillator configured to generate a modulation signal for modulating the optical signal inputted to the optical intensity modulator into DSB optical signals; a notch filter configured to filter an optical signal with a specific frequency; an optical fiber amplifier configured to amplify an output signal of the optical intensity modulator; an optical circulator configured to transmit the optical signal inputted to the optical fiber amplifier to the notch filter and transmit the optical signal reflected from the notch filter to an input of the optical intensity modulator; an optical coupler configured to apply the optical signal to the optical intensity modulator; and an OE converter configured to photomix the DSB signals outputted through the notch filter.

Abstract: According to an embodiment of the present invention, an optical parametric oscillator (OPO) (e.g., for a laser transmitting device) includes non-linear optical media, optical beam manipulating elements, and a narrow linewidth filter in the form of a rotatable grating. The grating enables rapid tuning of the oscillator to provide an output beam with a desired wavelength. A pump laser provides a pump laser beam, and the non-linear optical media convert the pump beam into light beams with a signal wavelength and an idler wavelength. The angular positions or orientations of the non-linear optical media relative to a longitudinal propagation axis of the optical parametric oscillator (OPO) are adjustable to effectively tune the resulting signal and idler wavelengths. An output coupler receives the resulting beams from the non-linear optical media, and emits beams with the desired wavelength (signal and/or idler wavelengths).

Abstract: An optical transmission system is provided. The optical transmission system includes a user side optical repeater device (ORD), a central office side ORD, and wavelength multiplexing and wavelength de-multiplexing functions (MUX/DEMUX). The user side optical repeater device (ORD) is to be connected with a user side optical network unit (ONU), transmits data in two ways, and is used for wavelength division multiplexing (WDM). The central office side ORD is to be connected with a central office side optical line terminal (OLT), transmits data in two ways, and is used for WDM. The wavelength multiplexing and a wavelength de-multiplexing functions (MUX/DEMUX), are used for relaying between the user side ORD and the central office side ORD.

Abstract: A compact source of polarization-entangled photons includes a laser source, producing a laser beam, a pair of nonlinear crystals, in optical contact with each other, with one of the pair of nonlinear crystals having an input face, with the laser beam incident on the input face, and another of the pair of nonlinear crystals rotated 90°, along an axis perpendicular to the input face, with respect to each other and a fiber coupling point, configured to receive a pair of single-mode fibers. Pairs of polarization-entangled photons are produced through spontaneous parametric down conversion of the laser beam and provided to the fiber coupling point.

Abstract: The invention relates to an optical wavelength conversion device adapted to receive at least one first pump beam (?1) as an input and emitting a different wavelength output beam (?S), which includes: an optical cavity (CE); an optically non-linear medium (CNL) placed inside the optical cavity; and a control system (BA1) for controlling said optical cavity having the wavelength of the first pump beam; said control system being adapted to receive, as an input, a first signal (S1) representing the power stored in the cavity having said first wavelength and a second signal (S2) representing the power of the output beam. The invention also relates to a coherent light source comprising such a device and one or two pump laser sources (L1, L2).

Abstract: An OPO is disclosed capable of rapid frequency tuning by non-mechanical means. The OPO includes a resonant cavity including one or more non-linear crystals in an optical path thereof. A pump laser pulse is transmitted into the resonant cavity simultaneously with a seed beam having a desired wavelength. The output beam from the resonant cavity has the same center wavelength as the seed beam. The wavelength of the seed beam may be modulated at a frequency larger than the pulse rate of the pump laser or larger than the inverse of the pulse duration. The OPO disclosed may be used to perform DIAL analysis wherein intra-pulse modulation of an output beam is used to obtain measurements of absorption at multiple frequencies for each pulse of a pump beam.

Abstract: A method of optimizing parametric gain in a nonlinear optical crystal that in response to application of a pump beam generates through a parametric generation process signal and idler beams, wherein the signal beam is non-collinear with the pump beam and the signal beam is subject to absorption due to the nonlinear material, the method involving shaping the pump beam to have an elliptical cross section, wherein the method further involves determining the width w of the pump beam depending on the absorption co-efficient of the optical crystal.

Abstract: A method of sustaining a plasma, by focusing a first wavelength of electromagnetic radiation into a gas within a volume, where the first wavelength is substantially absorbed by a first species of the gas and delivers energy into a first region of a plasma having a first size and a first temperature. A second wavelength of electromagnetic radiation is focused into the first region of the plasma, where the second wavelength is different than the first wavelength and is substantially absorbed by a second species of the gas and delivers energy into a second region of the plasma region within the first region of the plasma having a second size that is smaller than the first size and a second temperature that is greater than the first temperature.

Abstract: Improved production of entangled photon pairs (biphotons) via spontaneous parametric down conversion (SPDC) is provided. In one aspect, forward-wave SPDC is performed in a monolithic resonator (resonant for both signal and idler) having a double pass pump geometry to provide a spectrally bright source of biphotons. In another aspect, backward-wave SPDC is performed in a resonator (resonant for both signal and idler) to provide a spectrally bright source of biphotons. For either of these approaches, the biphotons can be made to have polarization entanglement by using quasi phasematching (QPM) with two QPM periods simultaneously.

Abstract: In an optical signal processing apparatus, carrier light propagates through a nonlinear optical medium. An optical combiner optically combines output control light for generating idler light of the carrier light with the carrier light. An optical splitter splits the idler light from the carrier light. A receiver acquires a signal multiplexed on the carrier light from the idler light split by the optical splitter.

Abstract: Apparatus and method for high-power multi-function millimeter-wavelength (THz-frequency) signal generation using OPO and DFG in a single cavity. In some embodiments, the OPO-DFG cavity includes an optical parametric oscillator (OPO) non-linear material that receives pump light IP having pump-light frequency and generates two different lower intermediate frequencies of light—an OPO-signal beam IS and a spatially/temporally overlapping OPO-idler beam II. A difference-frequency generator non-linear material then receives the two intermediate-frequency beams II and IS, and the DFG then generates a THz-frequency output signal that has a frequency equal to the difference between the two intermediate frequencies. In some embodiments, a single-piece crystal of non-linear material is used for both OPO and DFG functions.

Abstract: Pulses from a mode-locked Yb-doped laser (12) are spectrally broadened in an optical fiber (28), and temporally compressed in a grating compressor (32), then frequency-doubled (34) and used to pump an optical parametric oscillator (OPO) (40). The OPO output is tunable over a wavelength range from about 600 nm to about 1100 nm. Mode-locking in the Yb-doped laser (12) is accomplished with a SESAM (14) or by Kerr-lens mode-locking with a Kerr medium (82) and a hard aperture (84).

Abstract: Use of quasi-phase-matched (QPM) materials for parametric chirped pulse amplification (PCPA) substantially reduces the required pump peak power and pump brightness, allowing exploitation of spatially-multimode and long duration pump pulses. It also removes restrictions on pump wavelength and amplification bandwidth. This allows substantial simplification in pump laser design for a high-energy PCPA system and, consequently, the construction of compact diode-pumped sources of high-energy ultrashort optical pulses. Also, this allows elimination of gain-narrowing and phase-distortion limitations on minimum pulse duration, which typically arise in a chirped pulse amplification system. One example of a compact source of high-energy ultrashort pulses is a multimode-core fiber based PCPA system. Limitations on pulse energy due to the limited core size for single-mode fibers are circumvented by using large multimode core.