Abstract: A method for generating coherent, polarized, and tunable X-rays using a single laser pulse is provided. An ultrashort laser pulse is fired into a plasma. As the laser beam travels through the plasma, some of its photons are backscattered, e.g., through Raman backscattering, to generate a counter-propagating photon beam that is co-linear with the original laser beam. When the backscattered photons interact with high-energy accelerated periodic electron bunches, coherent X-rays are generated through Compton backscattering of the photons off of the electrons. The energy of the backscattered X-rays can be tuned by tuning one or more characteristics of the laser pulse and/or the plasma.

Abstract: A high power ultrashort chirped pulse amplifier laser system, with a chirped pulse amplifier laser module including an optical pulse stretcher, at least one optical power amplifier, and an optical pulse compressor, and a beam interferometer module in the optical path. The beam interferometer receives splits the pulse into at least two pulses, adds a time delay to at least one of the pulses and recombines the pulses to produce a temporally modulated pulse. The resulting modulated output pulse from the CPA laser module can have enhanced laser contrast due to greatly reduced subpicosecond pedestal in the immediate region of the peak pulse, or can have other desirable characteristics.

Abstract: A method for generating coherent, polarized, and tunable X-rays using a single laser pulse is provided. An ultrashort laser pulse is fired into a plasma. As the laser beam travels through the plasma, some of its photons are backscattered, e.g., through Raman backscattering, to generate a counter-propagating photon beam that is co-linear with the original laser beam. When the backscattered photons interact with high-energy accelerated periodic electron bunches, coherent X-rays are generated through Compton backscattering of the photons off of the electrons. The energy of the backscattered X-rays can be tuned by tuning one or more characteristics of the laser pulse and/or the plasma.

Abstract: A high power ultrashort chirped pulse amplifier laser system, with a chirped pulse amplifier laser module including an optical pulse stretcher, at least one optical power amplifier, and an optical pulse compressor, and a beam interferometer module in the optical path. The beam interferometer receives splits the pulse into at least two pulses, adds a time delay to at least one of the pulses and recombines the pulses to produce a temporally modulated pulse. The resulting modulated output pulse from the CPA laser module can have enhanced laser contrast due to greatly reduced subpicosecond pedestal in the immediate region of the peak pulse, or can have other desirable characteristics.

Abstract: A laser pulse from an ultrashort pulse laser (USPL) is fired into the atmosphere. The USPL pulse is configured to generate a plasma filament at a predefined target in the atmosphere, in which free, or “seed,” electrons are generated by multi-photon or tunneling ionization of the air molecules in the filament. A second pulse is fired into the atmosphere to form a heater beam that impinges on the plasma filament and thermalizes the seed electrons within the plasma filament, leading to the collisional excitation of the electrons in the filament. The excited electrons collisionally excite various electronic and vibrational states of the air molecules in the filament, causing population inversions and lasing, e.g., exciting the C3?u?B3?g(v=0?0) transition of the N2 in the atmosphere to cause lasing at 337 nm.

Abstract: An electron injector including an electron source and a conducting grid situated close to the electron source, one or more RF accelerating/bunching cavities operating at the same fundamental RF frequency; a DC voltage source configured to bias the cathode at a small positive voltage with respect to the grid; a first RF drive configured to apply an RF signal between the cathode and grid at the fundamental and third harmonic RF frequencies; and a second RF drive configured to apply an RF drive signal to the accelerating/bunching cavities. Electrons are emitted by the cathode and travel through the grid to the accelerating/bunching cavities for input into an RF linac.

Abstract: A system and methods for the quasi-remote compression and focusing of a moderate-intensity laser pulse to form a much higher intensity beam that can be directed at a target and used as a probe beam or used in a probe beam converter to generate other forms of electromagnetic radiation or energetic particles. A system for the quasi-remote propagation of high-intensity laser beams in accordance with the present invention comprises a main platform on which a first, “seed” laser pulse is generated, stretched, and amplified, and a remote platform, located at a distance from the main platform, which is configured to receive the amplified and stretched pulse and convert it into the high-intensity laser beam. The high-intensity laser beam in turn can then be converted into one or more probe beams directed at a target object.

Abstract: A system and methods for the quasi-remote compression and focusing of a moderate-intensity laser pulse to form a much higher intensity beam that can be directed at a target and used as a probe beam or used in a probe beam converter to generate other forms of electromagnetic radiation or energetic particles. A system for the quasi-remote propagation of high-intensity laser beams in accordance with the present invention comprises a main platform on which a first, “seed” laser pulse is generated, stretched, and amplified, and a remote platform, located at a distance from the main platform, which is configured to receive the amplified and stretched pulse and convert it into the high-intensity laser beam. The high-intensity laser beam in turn can then be converted into one or more probe beams directed at a target object.

Abstract: An electron injector including an electron source and a conducting grid situated close to the electron source, one or more RF accelerating/bunching cavities operating at the same fundamental RF frequency; a DC voltage source configured to bias the cathode at a small positive voltage with respect to the grid; a first RF drive configured to apply an RF signal between the cathode and grid at the fundamental and third harmonic RF frequencies; and a second RF drive configured to apply an RF drive signal to the accelerating/bunching cavities. Electrons are emitted by the cathode and travel through the grid to the accelerating/bunching cavities for input into an RF linac.

Abstract: An embodiment of the invention includes an apparatus. The apparatus includes a plurality of lasers comprising a plurality of laser paths. The apparatus further includes an incoherent combining beam director in the plurality of laser paths. The apparatus also includes a plurality of optical elements in the plurality of laser paths between the plurality of lasers and the beam director.

Abstract: A system is disclosed for developing a conditioned electron beam of high quality for an exemplary application to a free-electron source of coherent radiation. The system comprises: a source for producing an electron beam of relatively high energy, a microwave source for generating a microwave field, and a wiggler for generating transverse to the electron beam a periodic magnetic field which cooperates with the microwave field to interact with the electron beam and develop a conditioned electron beam of high quality.

Abstract: An x-ray lithography device in which a beam of electrons interacts with a microwave field of a quasi-optical maser such as a quasi-optical gyrotron. This maser comprises a pair of spaced mirrors defining a quasi-optical cavity therebetween, with one mirror being provided with an orifice to permit extraction of the x-ray beam produced. A Bragg reflector is connected to the mirror orifice to reduce the microwave power loss from the device through the orifice. Electrons injected in the maser cavity are caused to "wiggle" by the interacting microwave field, which functions as an undulator, so as to produce a non-coherent x-ray beam that travels along the longitudinal axis of the cavity and exits through the mirror orifice.