Patent application number | Description | Published |
20090310631 | High-Repetition-Rate Guided-Mode Femtosecond Laser - Femtosecond pulse trains in waveguide lasers with high fundamental repetition rates are achieved by exploiting the nonlinearity in the waveguide. Components of the apparatus include an optical resonator, a saturable absorber for starting and stabilizing mode-locking, and a gain element. Part of the laser cavity or the entire laser cavity is made of waveguide or fiber (collectively called “waveguide” herein). The net dispersion of the laser cavity can be anomalous. This anomalous dispersion in combination with the positive self-phase modulation nonlinearity in the waveguide creates soliton formation to shorten the pulse duration in the invented lasers. Conversely, a normal dispersive waveguide with negative self-phase modulation nonlinearity can also be used. | 12-17-2009 |
20100045974 | Compact Background-Free Balanced Cross-Correlators - A compact, background-free, balanced cross-correlator enables (a) the detection of a timing error between two ultrashort pulses with (sub-)femtosecond resolution and (b) the timing synchronization of ultrashort pulse lasers using the output signal of the detector to close a phase-locked loop and can therefore serve as an integral part of femtosecond timing distribution and synchronization systems. | 02-25-2010 |
20100253950 | Carrier-Envelope Phase Shift Using Linear Media - The carrier-envelope phase in a train of optical pulses is varied utilizing the dispersive properties of lossless plates while the total dispersion in transmission is maintained practically constant. The plates include sloped surfaces and are mounted for displacement such that the ratio of the thicknesses of the two plates through which the optical pulses will pass can be varied by displacing the plates so as to shift the carrier-envelope phase in the optical pulses. In one embodiment, the plates include a barium fluoride wedge and a fumed silica wedge, wherein the wedges are bond together to form a composite structure with thicker and thinner portions of the wedges inversely matched. | 10-07-2010 |
20110140009 | Efficient High-Harmonic-Generation-Based EUV Source Driven by Short Wavelength Light - Extreme ultraviolet radiation is generated based on high-order harmonic generation. First, a driver pulse is generated from a drive laser. Second, the infrared driver pulse is passed through a second harmonic generator with an output wavelength in the range from 400 to 700 nm. Third, the pulse is then passed through a gas medium, which can be inside a resonant cavity, to generate a high-order harmonic in the form of extreme ultraviolet radiation. | 06-16-2011 |
20110273763 | Cavity-Enhanced Parametric Amplification at Full Repetition Rate - Seed light pulses and pump light pulses are generated; the seed light pulses are preferably chirped; and both are directed into an enhancement cavity at a full repetition rate. The enhancement cavity defines a closed optical path that contains a nonlinear medium that provides phase matching at a wavelength different from both the central seed wavelength and the central pump wavelength. The generation of the pump light pulses and the seed light pulses are synchronized to pass the seed light pulses through the nonlinear medium simultaneously with the pump light pulses to parametrically amplify the seed light pulses in the nonlinear medium to produce an amplified signal pulse and idler pulse. Increased conversion with low average pump power can be achieved, as well as gain bandwidth enhancement approaching octave-spanning levels. Additionally, in the case of chirped pump pulses with sufficient bandwidth, optimal output coupling can be designed to achieve the best impedance matching at each temporal coordinate and attain the highest possible conversion and bandwidth. | 11-10-2011 |
20110274135 | Broadband Dispersion-Free Optical Filter Cavities Based on Dielectric Mirrors with Complementary Dispersion - A substantially dispersion-free optical filter cavity includes a first multilayer mirror and a second multilayer mirror, wherein each mirror includes layers of a less-refractive material and layers of a more-refractive material, the more-refractive material having a higher index of refraction than the less-refractive material. The mirrors are separated by a spacing, and the thickness of a plurality of the layers in the second multilayer mirror differ from corresponding layers in the first multilayer mirror to provide the cavity with complementary group-delay dispersion across the cavity with a phase difference within, e.g., ±0.015 rad across a range of wavelengths spanning at least, e.g., 50 nm. | 11-10-2011 |
20110310914 | Mode-Locking with Reduced Nonlinearity Using Gain-Matched Output Couplers - A laser cavity includes a gain medium for amplifying a light pulse in a light path, wherein the gain medium has a gain profile for amplifying the light pulse as a function of wavelength; at least one mirror on one side of the gain medium; and an output coupler. The output coupler has an output coupling profile for inducing loss in the light pulse as a function of wavelength that substantially matches the saturated gain profile of the gain medium across a range of lasing wavelengths. The purpose of this device is to achieve a flattened net-gain profile to substantially improve mode-locking performance with respect to self-starting, beam-quality, and broadband operation. | 12-22-2011 |
20120288065 | Compact Coherent Current and Radiation Source - Coherent electronic current, which can be used to generate coherent radiation, is generated by first generating and transmitting an array of discrete electron beamlets from a nanocathode array along a longitudinal axis. The array of electron beamlets is then focused to reduce the spacing that separates the electron beamlets. The transverse-axis spacing of the electron beamlets is then transferred to the longitudinal axis via an emittance exchange beamline, creating a periodically modulated distribution of coherent electronic current. The coherent electronic current can then be directed into a stream of photons to generate coherent radiation. | 11-15-2012 |
Patent application number | Description | Published |
20130301117 | METHODS, SYSTEMS, AND APPARATUS FOR HIGH ENERGY OPTICAL-PULSE AMPLIFICATION AT HIGH AVERAGE POWER - An inventive composite optical gain medium capable includes a thin-disk gain layer bonded to an index-matched cap. The gain medium's surface is shaped like a paraboloid frustum or other truncated surface of revolution. The gain medium may be cryogenically cooled and optically pumped to provide optical gain for a pulsed laser beam. Photons emitted spontaneously in the gain layer reflect off or refract through the curved surface and out of the gain medium, reducing amplified spontaneous emission (ASE). This reduces limits on stored energy and gain imposed by ASE, enabling higher average powers (e.g., 100-10,000 Watts). Operating at cryogenic temperatures reduces thermal distortion caused by thermo-mechanical surface deformations and thermo-optic index variations in the gain medium. This facilitates the use of the gain medium in an image-relayed, multi-pass architecture for smoothed extraction and further increases in peak pulse energy (e.g., to 1-100 Joules). | 11-14-2013 |
20140185635 | METHODS AND APPARATUS FOR BROADBAND FREQUENCY COMB STABILIZATION - Feedback loops can be used to shift and stabilize the carrier-envelope phase of a frequency comb from a mode-locked fibers laser or other optical source. Compared to other frequency shifting and stabilization techniques, feedback-based techniques provide a wideband closed-loop servo bandwidth without optical filtering, beam pointing errors, or group velocity dispersion. It also enables phase locking to a stable reference, such as a Ti:Sapphire laser, continuous-wave microwave or optical source, or self-referencing interferometer, e.g., to within 200 mrad rms from DC to 5 MHz. In addition, stabilized frequency combs can be coherently combined with other stable signals, including other stabilized frequency combs, to synthesize optical pulse trains with pulse durations of as little as a single optical cycle. Such a coherent combination can be achieved via orthogonal control, using balanced optical cross-correlation for timing stabilization and balanced homodyne detection for phase stabilization. | 07-03-2014 |