2 papers
physics.optics2013
Optical beam dynamics in a gas repetitively heated by femtosecond filaments
N. Jhajj, Y. -H. Cheng, J. K. Wahlstrand +1
We investigate beam pointing dynamics in filamentation in gases driven by high repetition rate femtosecond laser pulses. Upon suddenly exposing a gas to a kilohertz train of filame…
physics.optics2011
Optical nonlinearity in Ar and N near the ionization threshold
J. K. Wahlstrand, Y. -H. Cheng, Y. -H. Chen +1
We directly measure the nonlinear optical response in argon and nitrogen in a thin gas target to laser intensities near the ionization threshold. No instantaneous negative nonlinea…