Continuing technical advances in the creation of (sub-) femtosecond VUV and X-ray pulses with Free-Electron Lasers and laser-based high-harmonic-generation sources have created new opportunities for studying ultrafast dynamics during chemical reactions. Here, we present an approach to image the geometric structure of gas-phase molecules with fewfemtosecond temporal and sub-Ångström spatial reso...

The ideal electric laser efficiently converts electrical power into optical power in the form of a beam that can propagate a long distance with minimal diffraction-limited spreading. Various laser applications require scaling to high power (kWs to MWs) while maintaining a diffrac-tion-limited beam; thus, many efforts have been directed toward that goal. The main impediment to this high-power sc...

Time-domain experiments on solid-state dynamics at the fastest time-scales are typically performed using all optical techniques. These experiments have been made possible by, and have driven significant advances in, pulsed laser technology. Since optical techniques only indirectly probe structure, there is a significant scientific motivation for using higher spatial resolution probes such as X-...

We describe a new biosensor immunoassay involving optical diffraction to detect clinically Important analytes in human body fluids. A siliconwafer is used as a support for immobilization of antigen or antibody. The protein-coated surface is illuminated through a photo mask to create distinct periodic areas of active and inactive protein. When the surface is incubated with a positive sample, ant...

We demonstrate the use of intensity-modulated laser diodes to implement pump-probe microscopy and achieved sub-diffraction resolution imaging with shot-noise limited sensitivity with a scheme of balanced detection. This technique has several applications for various types of induced transmission change, including excited-state absorption, ground state absorption bleaching and stimulated emissio...

Time-resolved reflection high-energy electron diffraction has been developed to study the structure of surfaces. In this technique, an ultrafast laser pulse is split into two components. The first component interacts with the surface and serves as a transient heating source. The second component strikes the cathode of a photoactivated electron gun, photoelectrically producing pulses of electron...

We demonstrated for the first time the application of a self-diffraction (SD) process in a bulk Kerr medium to improve the temporal, spectral, and spatial qualities of femtosecond laser pulses. A proof-of-principle experiment succeeded in improving the temporal contrast of a femtosecond pulse by four orders of magnitude even in the picosecond region using a 0.5-mm-thick fused silica glass plate...

Managing pipe damaged by Stress Corrosion Cracking (SCC) has been a formidable challenge to the pipeline industry. The development of a practical solution for the measurement and evaluation of SCC has been marred by the complexity of crack shapes, their distribution within a crack colony, and the lack of non-destructive technology capable of reliably measuring the crack depths. Laser ultrasonic...

By making use of a new technique for measuring the complete spatiotemporal electric field of light with micrometer spatial and femtosecond temporal resolution, we directly demonstrate the formation of the so called boundary diffraction wave and Arago’s spot, as well as the superluminal propagation of a “diffrac tion free” pulse. We believe that such spatiotemporally resolved measurements and th...