High-order harmonic generation from solid targets with 2 mJ pulses.
Harmonics up to the 18th order are generated from solid targets by focusing 2 mJ, 50 fs pulses at 800 nm to a spot size of 1.7 μm (FWHM). To our knowledge, this is the first demonstration of high-harmonic generation with a very short focal length paraboloid (f/1.4) and kilohertz laser system. The harmonics have a low divergence (<4°) compared to the driving beam and conversion efficiencies (>10(-7) per harmonic) comparable to gas harmonics. No contrast enhancement techniques are employed, and the system is capable of operating at 500 Hz.
Easter
James H
JH
Center for Ultrafast Optical Science, University of Michigan, 2200 Bonisteel Boulevard, Ann Arbor, Michigan 48109, USA. jheaster@umich.edu
Mordovanakis
Aghapi G
AG
Hou
Bixue
B
Thomas
Alexander G R
AG
Nees
John A
JA
Mourou
Gérard
G
Krushelnick
Karl
K