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Title: Spectral phase effects in above threshold ionization
Abstract We present theoretical studies of above threshold ionization (ATI) using sculpted laser pulses. The time-dependent Schrödinger equation is solved to calculate the ATI energy and momentum spectra, and a qualitative understanding of the electron motion after ionization is explored using the simple man’s model and a classical model that solves Newton’s equation of motion. Results are presented for Gaussian and Airy laser pulses with identical power spectra, but differing spectral phases. The simulations show that the third order spectral phase of the Airy pulse, which can alter the temporal envelope of the electric field, causes changes to the timing of ionization and the dynamics of the rescattering process. Specifically, the use of Airy pulses in the ATI process results in a shift of the Keldysh plateau cutoff to lower energy due to a decreased pondermotive energy of the electron in the laser field, and the side lobes of the Airy laser pulse change the number and timing of rescattering events. This translates into changes to the high-order ATI plateau and intra- and intercycle interference features. Our results also show that laser pulses with identical carrier envelope phases and nearly identical envelopes yield different photoelectron momentum distributions, which are a direct result of the pulse’s spectral phase.  more » « less
Award ID(s):
2207209
PAR ID:
10431077
Author(s) / Creator(s):
Date Published:
Journal Name:
Journal of Physics B: Atomic, Molecular and Optical Physics
Volume:
56
Issue:
9
ISSN:
0953-4075
Page Range / eLocation ID:
095601
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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