The goal of this paper is to explore the power of stochastic search methods, in particular genetic algorithms, to solve a challenging problem in experimental physics. The problem is to find an optimum frequency to stabilize atoms by high-intensity laser fields. The standard approach to search for optimal laser parameters has been by trial and error. This is the first known application of a gene...

We study single-shot damage morphology of MgF2 irradiated under 800 nm laser using scanning electronic microscope (SEM). The dependence of damage threshold on laser pulse width is measured by the linear relationship between the area of damage spot and the logarithm of laser energy. The pulse duration ranges from 55 fs to 750 fs. We develop the multiple-equation model (Phys. Rev. Lett. Vol.92, p...

Frequent assertions by river users that rivers in northern England now rise and fall more quickly than in the past, have never been validated by analysis on catchments of more than 10 km 2. The method using indices of flow variability provides a basis for making direct measurements of the annual number and duration of pulses, i.e. rises above a given flow, and for comparing catchments of differ...

The absolute time-dependent nonlinear response of O2, N2, N2O, and Ar to intense nonionizing, ultrashort optical pump pulses is measured with single-shot spectral interferometry. The instantaneous and delayed rotational responses are distinguished as a function of pump-pulse duration and probe central wavelength. Our measurements are central to the modeling and understanding of nonlinear propag...

2014 A laser pulse method for diffusivity determination is analysed. The method which permits the measurement of the laser pulse energy distribution as well as its shape is developed. This method can be easily implanted into laser pulse diffusivity set-up and it allows to check periodically the pulse characteristics that is of primary importance for the accuracy of the diffusivity measurements....

We demonstrate power scaling of an Nd:YAG picosecond master oscillator power amplifier system to over 200 W. The ‘z-slab’ amplifier design is a power scalable, edge-pumped zigzag slab amplifier architecture, and it is demonstrated here in two alternative multi-stage implementations at 1064 nm using a picosecond seed laser. In a simple design, an average power of 225 W was generated with up to 4...

We have measured the absolute dissociation probability of SF 6 gas irradiated by CO 2 laser pulses varying in duration from 0.5 nsec to 100 nsec. We find a threshold for dissociation of ~ 1.4 J/cm 2, independent of pulse duration. For fixed energy density, the dissociation probability increases as the pulse duration decreases, but not nearly to the degree expected from theory. We have also dete...

ABSTRACT Multiple foci are created along the propagation direction of a laser beam using simultaneous spatial and temporal focusing of an ultrafast laser pulse in conjunction with parametric pulse shaping. The pulses are characterized with scanning SEA TADPOLE. The longitudinal and transverse positions of the foci are controlled using phase and amplitude shaping in a 4-f laser pulse shaping sys...