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We present photonic crystal structures that exhibit small group velocity of light, which can be used as compact optical delay component. We experimentally measure the group velocity reduction to be less than 0.008c. By breaking the rotation symmetry of the ...
Epitaxial Laser Metal Forming (E-LMF) consists in impinging a jet of metallic powder onto a molten pool formed by controlled laser heating and thereby, generating epitaxially a single crystal deposit onto a single crystal substrate. It is a near net-shape ...
Experimental demonstration of optical speedup at transparency (OSAT) has been performed on a 1 mm long semiconductor optical amplifiers (SOA). OSAT is a recently proposed scheme that decreases the recovery time of an SOA while maintaining the available gai ...
In order to improve the reliability of micro-spot welding of metal parts in production such as e.g. in electron guns for TV picture tubes, real-time information about the evolution of the welding process should be available to allow on-line modification of ...
In order to improve the reliability of micro-spot welding of metal parts in production such as e.g. in electron guns for TV picture tubes, real-time information about the evolution of the welding process should be available to allow on-line modification of ...
This study investigates the composition of free surfaces of neodymium-doped yttrium–aluminum–garnet, using energy minimization techniques. Atomistic modeling shows that the dopant is concentrated in a zone within 0.5 nm ̊of the surface, the enrichment fact ...
A new laser micro-spot welding procedure for copper has been developed in order to eliminate the shortcomings of existing techniques based on laser pulse shaping or in-situ temperature control. This procedure consists in dividing the welding process in fou ...
Epitaxial Laser Metal Forming (E-LMF) consists in impinging a jet of metallic powder onto a molten pool formed by controlled laser heating and thereby, generating epitaxially a single crystal deposit onto the damaged component. This new technique aims to b ...
Nd:YAG laser welding of high reflectivity metals is difficult because of the highly non-linear light-material interaction yielding a narrow process window and poor reliability. However, achieving high reliability is mandatory for applying this technique in ...
Diode-pumped solid body laser comprises an acoustic-optical modulator, a laser crystal, a delay plate and a crystal that doubles the frequency of the laser beam. Pulse lengthening is carried out by internal coupling of a doubler mechanism within the laser ...