Biomedical subjects
Publications and source records attributed to Jonathan D Zuegel.
A 250 mJ, 5 Hz repetition rate optical parametric chirped-pulse amplifier with near-Fourier-transform-limited, 430 fs pulses and a beam that can be focused to near the diffraction limit is demonstrated. A pump laser with engineered spatial and temporal profiles allows an overall pump-to-signal conversion efficiency of 34% to be achieved.
A high-energy, high-average-power laser system, optimized to efficiently pump a high-performance optical parametric chirped-pulse amplifier at 527 nm, has been demonstrated. The crystal large-aperture ring amplifier employs two flash-lamp-pumped, 25.4-mm-diameter Nd:YLF rods. The transmitted wave front of these rods is corrected by magnetorheological finishing to achieve nearly diffraction-limited output performance with frequency-doubled pulse energies up to 1.8 J at 5 Hz.
A diode-pumped Nd:YLF regenerative amplifier (regen) has been developed and is in use in the 60-beam, 30-kJ UV Omega laser system's driver line. The high stability, the compactness, and the reliability of this all-solid-state modular design are the key features of this concept. Stable, millijoule-level output-pulse energies with an overall gain of 10(9) have been demonstrated. Excellent long-term output-pulse-energy stability of better than 1% rms fluctuations has been achieved with excellent beam quality (<1% ellipticity).
We report a ytterbium fiber laser mode locked at its 281st harmonic, which corresponds to a repetition rate greater than 10 GHz. The laser produces linearly polarized, 2-ps pulses with up to 38-mW of average output power. The mode-locked pulses are tunable over a 58-nm window centered on 1053 nm.
An efficient, 10.4-GHz bulk phase modulator is demonstrated that produces frequency-modulated optical bandwidths in excess of 300 GHz in a double-pass configuration with modest microwave drive power. The waveguide resonator design employs velocity matching to maximize phase-modulation efficiency and a modified form of cutoff waveguide coupling to achieve a high microwave cavity Q factor that reduces power requirements. The measured microwave performance of the modulator agrees well with performance predicted from fully anisotropic, three-dimensional numerical simulations.
A phase-only spatial light modulator is used in conjunction with a spatial filter to provide independent control of the phase and amplitude of a laser beam. Continuous amplitude modulation of the beam is achieved with a resolution relevant to beam shaping of high-energy laser beams. Amplitude beam correction in a closed loop is demonstrated.