Strong field physics in a scaled interaction

B. Sheehy, Brookhaven National Laboratory
T. O. Clatterbuck, Brookhaven National Laboratory
C. Lyng, Brookhaven National Laboratory
J. D.D. Martin, Brookhaven National Laboratory
D. W. Kim, Brookhaven National Laboratory
L. F. DiMauro, Brookhaven National Laboratory
M. B. Gaarde, Lunds Tekniska Högskola
K. J. Schafer, Louisiana State University
P. Agostini, Service des Photons Atomes et Molécules
K. C. Kulander, Lawrence Livermore National Laboratory


Strong-field interactions at long wavelengths are studied experimentally and theoretically, and compared with studies at shorter wavelengths. Under similar dynamical conditions, we find a more pronounced role for atomic structure in the long wavelength studies. Ion core structure is reflected in photoelectron energy spectra in a manner consistent with the rescattering picture, and stronger coupling between ground and excited states influences high harmonic generation spectra. Spectral and temporal measurements of high harmonics generated from a mid-infrared fundamental are presented.