Yutong Li | PubMed Health

PubMed2005

Polarization-dependent supercontinuum generation from light filaments in air.

We investigate polarization-dependent properties of the supercontinuum emission generated from filaments produced by intense femtosecond laser pulses propagating through air over a long distance. The conversion efficiency from the 800-nm fundamental to white light is observed to be higher for circular polarization than for linear polarization when the laser intensity exceeds the threshold of the breakdown of air.

Journal Article↗

PubMed2002

Characteristics of self-guided laser plasma channels generated by femtosecond laser pulses in air.

With ultrashort laser pulses (25 fs) and low energy (E=15 mJ), we observe laser plasma channels with a length over 5 m in air. The diameter of the plasma channel is measured to be 120 microm. The average electron density in the channel is inferred to be about 10(18) W/cm(3) with an interferometric method. At the same time, the temporal evolution of the electron density in the plasma channel is investigated. The resistivity in the plasma channel is measured to be less than 1 Omega cm. It is suggested that the lifetime of the plasma channel can be greatly prolonged by launching another long laser pulse along the plasma channel.

Journal Article↗