Ultrashort laser pulses with multi-Gigawatt peak power are intense enough to ionize air as they propagate. We study this mechanism of plasma generation and its potential applications that include the remote initiation of atmospheric lasing and guiding various forms of radiation ranging from long-pulse laser beams to microwaves.
Natural dielectric breakdown of air usually follows a zigzagging trajectory. Laser-generated plasma can provide a preferential path for the discharge to follow, channeling the discharge to the remote target of interest.
We apply intense laser pulses with exotic beam shapes to the generation of plasma channels and channel arrays with controlled geometries. For example, self-bending Airy beams produce plasma channels that curve around obstacles, while intense optical vortices generate bottle-like distributions of plasma channels that can be used to channel highly divergent microwave beams.
We conduct experiments on the nonlinear conversion of ultrashort laser pulses to otherwise inaccessible parts of the optical spectrum such as deep ultraviolet and long-wave infrared.
Ionization of air by ultrashort mid-infrared laser pulses is accompanied by efficient generation of multiple near-infrared and visible harmonics. We study emission patterns of these harmonics to extract information about the properties of the generated plasma.
Physical processes involved in permanent material modification by ultra-short laser pulses are extremely complex and occur across vastly dissimilar time scales from femtoseconds to microseconds. Our research is aimed at the development of new predictive models describing the physics of femtosecond laser-matter interactions and at the experimental validation of those models.
