Abstract: A system for dispersion compensation in a terahertz system includes an optical fiber configured to transmit an optical pulse, a compensator optically coupled to the optical fiber, the compensator configured to compensate for a dispersion of the optical pulse caused as the optical pulse propagates through the optical fiber, and an optically induced terahertz device optically coupled to the compensator, whereby the optically induced terahertz device is configured to transmit or receive terahertz radiation.

Abstract: An intracavity resonant Fabry-Perot saturable absorber (R-FPSA) induces modelocking in a laser such as a fiber laser. An optical limiter such as a two photon absorber (TPA) can be used in conjunction with the R-FPSA, so that Q-switching is inhibited, resulting in laser output that is cw modelocked. By using both an R-FPSA and a TPA, the Q-switched modelocked behavior of a fiber laser is observed to evolve into cw modelocking.

Abstract: An optical parametric amplifier pumped by ultrashort optical pulses provides time-gated image amplification or time-gated image frequency conversion, resulting in optical sectioning of an object under test and/or background rejection of improperly timed light. An ultrashort laser pulse of one frequency is used to illuminate an object under test. An ultrashort pulse light beam at a signal frequency transmitted through or scattered from the object is optically mixed with an ultrashort laser pulse at a pump frequency in a nonlinear optical medium. This mixing produces an amplified image of a particular optical section of the object at the signal frequency in addition to producing a frequency converted image of the same optical section at an idler frequency. This time-gated amplification can be used in conjunction with a confocal imaging system, or a conventional imaging system.

Abstract: An optical parametric amplifier pumped by ultrashort optical pulses provides time-gated image amplification or time-gated image frequency conversion, resulting in optical sectioning of an object under test and/or background rejection of improperly timed light. An ultrashort laser pulse of one frequency is used to illuminate an object under test. An ultrashort pulse light beam at a signal frequency transmitted through or scattered from the object is optically mixed with an ultrashort laser pulse at a pump frequency in a nonlinear optical medium. This mixing produces an amplified image of a particular optical section of the object at the signal frequency in addition to producing a frequency converted image of the same optical section at an idler frequency. This time-gated amplification can be used in conjunction with a confocal imaging system, or a conventional imaging system.

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.

Abstract: A laser system that enables dual-wavelength asynchronous modelocked operation with controllable repetition rates reduces gain competition and wavelength coupling with either inhomogeneously or homogeneously broadened gain media. Another purpose of the laser system is to minimize pulse interaction effects. The system includes a laser excitation device for generating output wavelengths from the gain medium with non-uniform gain profile. Further, the system includes devices for modelocking and coupling the wavelengths generated by the gain medium. The system includes at least one laser cavity for each of the generated wavelengths.

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.