Peter F. Moulton

Spectroscopic and laser characteristics of Er,Cr:YSGG

The spectroscopic and laser properties of crystal Er,Cr:YSGG are discussed and it is shown that excitation is efficiently transferred from chromium to erbium. Laser operations at 2796 nm are achieved with much lower thresholds than in other erbium-doped crystals. >

Effects of Pulse Rate and Temperature on Nonlinear Absorption of Pulsed 262-nm Laser Light in β-BaB2O4

The efficiency of multi-watt ultraviolet radiation generation by harmonics processes in β-BaB2O4 (BBO) can be improved by reducing thermal dephasing. The dephasing arises from local heating of BBO by the linear absorption of green (second harmonic) and ultraviolet (fourth harmonic) radiation by crystal defects that are induced by two-photon absorption of high peak power ultraviolet radiation. Such absorption can be reduced by decreasing the repetition rate to ~1 kHz to allow the defects to decay between the laser pulses and/or heating BBO crystal to 150–200 °C to increase the decay rate of the induced defects.

Reduction of Nonlinear Absorption in Li2B4O7 by Temperature- and Repetition Rate-Control

We address the critical issue of thermal dephasing of the UV harmonic generation process due to nonlinear absorption in Li2B4O7 crystals. Reduction of nonlinear absorption is achieved by increasing the crystal temperature up to 200 °C and reducing the pulse repetition rate. Our results show the way for significant improvement of the conversion efficiency for the fourth harmonic generation of Nd lasers using Li2B4O7 crystals.

Threshold analysis of pulsed lasers with application to a room-temperature Co:MgF/sub 2/ laser

Rate-equation calculations are used to model accurately the near-threshold behavior of a Co:MgF/sub 2/ laser operating at room temperature. The results demonstrate the limitations of the conventional threshold analysis in cases of practical interest. This conclusion is applicable to pulsed solid-state lasers in general. The calculations, together with experimental data, are used to determine emission cross sections for the Co:MgF/sub 2/ laser. >

Stable-relaxation-oscillation Nd lasers for long-pulse generation

A simple method to produce high-energy neodymium (Nd) laser pulses with durations on the order of 1 mu s is described. Solid-state lasers can be pumped by relatively short flashlamp pulses to produce well-behaved relaxation oscillations in a diffusion-limited beam. Under the right conditions, each output laser pulse consists of a series of discrete subpulses that are ideally suited to efficient, high-energy amplification. Experimental results for an Nd:LiYF/sub 4/ oscillator/amplifier system are presented along with numerical simulations. These demonstrate that the system operation is predictable and well behaved. Data are also included for a Nd:glass tunable oscillator based on this concept. >