Predicting laser-induced bulk damage and conditioning for deuterated potassium dihydrogen phosphate crystals using an absorption distribution model.

We present an empirical model that describes the experimentally observed laser-induced bulk damage and conditioning behavior in deuterated potassium dihydrogen phosphate (DKDP) crystals. The model expands on an existing nanoabsorber precursor model and the multistep absorption mechanism to include two populations of absorbing defects, one with linear absorption and another with nonlinear absorption. We show that this model connects previously uncorrelated small-beam damage initiation probability data to large-beam damage density measurements over a range of nanosecond pulse widths. In addition, this work predicts the damage behavior of laser-conditioned DKDP.

Very long lasers.

The properties and oscillation characteristics of very long cw xenon lasers are discussed and pertinent long laser experiments described. High-gain 3.508-microm xenon laser amplifiers were used in these experiments. Laser cavity lengths of up to 30 km were studied. Spectrum analyses revealed complex oscillation spectra exhibiting the characteristics of both homogeneous and inhomogeneous laser mode structures. Long laser Doppler experiments, Q-switching studies, and modulation experiments were performed. Applications to atmospheric pollution detection are discussed.