Spontaneous chaos and extreme events in a solid-state laser with the transverse-mode-degenerate cavity configuration.

In this Letter, we theoretically analyze cavity beam propagation in a gain medium and cavity using the rate equation and generalized Huygens integral, respectively. Spontaneous chaos and extreme events (EEs) occurred around the transverse-mode-degenerate cavity configuration because of transverse-mode competition. A closed occurrence region relating to varying pump power and cavity length was observed.

Cavity-sensitive amplified spontaneous emission with radiation reabsorption.

We experimentally and numerically investigate amplified spontaneous emission (ASE) in the presence of radiation reabsorption by using an end-pumped ruby laser. From the fluorescence time decay in the axial direction, we find that the average path length of ASE is much larger than the reabsorption length and exhibits sharp variation near the semi-concentric cavity configuration; however, the side lifetime is independent of cavity configuration. In addition, an axial power bump corresponding to a side power valley and the enhanced fluorescence R-line spectrum are observed and explained.

Comparison of the accuracy of matrix-assisted laser desorption ionization-time of flight mass spectrometry with that of other commercial identification systems for identifying Staphylococcus saprophyticus in urine.

Among 30 urinary isolates of Staphylococcus saprophyticus identified by sequencing methods, the rate of accurate identification was 100% for Bruker Biotyper matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), 86.7% for the Phoenix PID and Vitek 2 GP systems, 93.3% for the MicroScan GP33 system, and 46.

Saturation of radiation trapping and lifetime measurements in three-level laser crystals.

In this study, we take the pump rate into consideration for the first time to give a theoretical description of radiation trapping in three-level systems. We numerically verify that under strong pumping, the population of the ground state is depleted, which leads to saturation of the radiation trapping within the pumped region. This saturation inevitably clamps the lifetime lengthening that is experimentally verified on a 0.

Generating a geometric mode for clarifying differences between an operator method and SU(2) wave representation.

We study both numerically and experimentally a specific geometric mode, named VW mode, in an end-pumped Nd:YVO4 laser with a plano-concave cavity near the 1/3-degeneracy. Three theoretical methods are used to analyze the transverse profiles, the operator method [J. Opt.

Nonlinear optical property of azo-dye doped liquid crystals determined by biphotonic Z-scan technique.

This work investigates the optical Kerr property of azo-dye doped nematic liquid crystal films using the biphotonic Z-scan technique. The results indicate that the nonlinear effect measured using the Z-scan technique with a red light can be modulated or switched with the simultaneous application of a green light, because of photoisomerization and thermal effects, as determined by dynamic measurements. The former dominates in the early stage when the green light is applied, while the latter dominates in the later stage.

Bottle beam from a bare laser for single-beam trapping.

We demonstrate that a laser beam converging from a specific transverse mode is a bottle beam, as described in J. Opt. Soc.

Direct generation of optical bottle beams from a tightly focused end-pumped solid-state laser.

We demonstrate that various optical bottle beams can be directly generated from a tightly focused end-pumped Nd:YVO4 laser. By controlling the size of pump beam and intracavity aperture in a planoconcave cavity, we obtain well contrasting optical bottles with semiconfocal, 1/3-, and 1/5-degenerate cavity configurations. These beams result, respectively, from the superposition of the fundamental mode and the corresponding lowest degenerate transverse eigenmode, which is in-phase at their beam waists.