ИСТИНА

Laser pulse interaction with gas jet targets provides a lot of interesting effects resulting in generation of intense electromagnetic radiations in a wide frequency band. Two important examples of such processes are considered using 2D particle-in-cell simulation. The first one is formation of relativistic electron mirrors from gas jets by accelerating laser pulses and generation of coherent ultrashort XUV pulses through Thomson backscattering of a probe laser pulse off such mirrors. If the target is thin enough and its density is moderate then full evacuation of electrons from a gas plasma near the laser beam axis takes place and a relativistic electron mirror is formed. For thick targets, relativistic boundary of the gas plasma can be produced providing for effective Thomson backscattering of a probe laser pulse. Parameters of produced relativistic electron mirrors and generated coherent ultrashort XUV pulses are studied. The second example considers generation of intense low-frequency (infrared and terahertz) radiation in a multiterawatt laser pulse interaction with a nanowire target. Characteristics of generated radiation are found for different parameters of laser pulse and nanowire.