Generation of tunable octave-spanning mid-infrared pulses by filamentation in gas media.
The continued development of femtosecond mid-infrared (IR) sources with ultrabroad spectral width is critical for probing and controlling complex molecular structural dynamics on an ultrafast timescale. We report on a sub-20 fs, coherent mid-IR source with an octave-spanning spectral bandwidth (>2000 cm(-1)) tunable from 2-8 micrometers (37.5-150 THz), with energy >0.4 μJ/pulse at 1 kHz. The mid-IR pulses are generated by four-wave mixing during the filamentation of intense 800 nm and 400 nm pulses in various gas media. Spectral tunability is achieved by the choice of gas, pressure and input 800 nm pulse energy.
Department of Chemistry, University of Washington, Seattle, Washington 98195, USA.
Mark
M
Cheng
Anthony
A
Reynolds
Heather
H
Widgren
Munira
M
Khalil
D005740:Gases; D008027:Light; D017711:Nonlinear Dynamics; D013055:Spectrophotometry, Infrared / Q000379:methods*; D013997:Time Factors
D005740:Gases