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Short Laser Pulses (short + laser_pulse)

Distribution by Scientific Domains
Physics and Astronomy100%

Selected Abstracts

Energy absorption and emission of harmonics by clusters subject to intense short laser pulses

LASER PHYSICS LETTERS, Issue 9 2008
S.V. Popruzhenko
Abstract Experimental and theoretical achievements in studies of atomic and metal clusters interacting with short intense infrared laser pulses are reviewed. The focus is made on the theoretical concepts describing the energy transfer from the laser field to the cluster nanoplasma and emission of laser harmonics from it. Both effects are considered assuming the collisionless regime, where the interaction of nanoplasma electrons with the self-consistent field dominates the individual collisions. The pivotal role of nonlinear resonances is underlined and described in detail. Possible ways for a further development of the theory and experimental perspectives are briefly discussed. (© 2008 by Astro Ltd., Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

Laser fluence and shot number dependence of laser-induced optical properties modification of transparent materials

LASER PHYSICS LETTERS, Issue 12 2006
K. Jamshidi-Ghaleh
Abstract Micro-fabrication in transparent materials by femtosecond laser-induced modification of the optical properties inside transparent materials, preferentially optical glasses, has received much attention. Ultra short laser pulses are capable of inducing these modifications without cracking or even melting the glasses. This kind of modification, which appears as darkening inside glass relates to the trapped electrons or holes at defect sites in the glass matrix. The femtosecond laser technology allows controlling and modifying the optical properties of glasses on a sub-micrometer scale. Laser fluence and laser shot number are important parameters for femtosecond laser-induced modification of glasses. This paper presents the 800 nm femtosecond laser-induced optical modification inside soda lime glasses at different laser fluence levels and laser shot numbers. Modification thresholds at different applied laser fluences and shot numbers are measured. Pulse energy accumulation model is proposed to predict the behaviour of darkened area spots with applied laser fluence and shot numbers. Our experimental results and the pulse energy accumulation model are in good agreement. (© 2006 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source]

Retarded surface photovoltage response from dye molecules adsorbed on metal oxide surfaces

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 11 2004
Th. DittrichArticle first published online: 11 AUG 200
Abstract A retarded surface photovoltage response has been observed on metal oxide layers (SnO2:F, TiO2) covered with adsorbed dye molecules while only the dye molecules were excited by short laser pulses. The retardation ranged between 30 and 570 ns depending on the nature of the metal oxide and on surface treatment. Therefore, charge separation in space of electrons injected from dye molecules into metal oxides is strikingly different from ultrafast electron injection measured by time-resolved optical techniques. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

Self-organized regular surface patterning by pulsed laser ablation

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 3 2009
Juergen Reif
Abstract The impact of intense ultra short laser pulses on solid surface - as in laser ablation - results in a transient perturbation of the material to a state far from equilibrium. Due to ultrafast relaxation of the transient disorder in a few picoseconds, self-organized surface patterns occur, with a typical feature size at the order of 100 nm or less, similar as observed in ion sputtering and explained by non-linear dynamics models. The feature size of these structures is determined by the deposited energy dose, their shape and orientation crucially depends on the state of polarization of the incident light. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]