Photoemission and high-order harmonic generation from solid surfaces in intense laser fields

Journal Article · Mon Aug 15 00:00:00 EDT 2005 · Physical Review. A

DOI:https://doi.org/10.1103/PhysRevA.72.023412· OSTI ID:20718168

Faisal, F H.M. ^[1]; Kaminski, J Z ^[1]; Saczuk, E ^[2]

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1. Fakultaet fuer Physik, Universitaet Bielefeld, 33615 Bielefeld (Germany)
2. Institute of Theoretical Physics, Warsaw University, Hoza 69, 00-681 Warsaw (Poland)

We give a Floquet analysis of photoemission of electrons and high-order harmonic generation from a solid surface interacting with intense laser fields. A general theoretical algorithm, within a three-dimensional quasi-free-electron model, is presented. It takes account of the effective masses of the electron both within and outside the solid, as well as treating both reflected and refracted laser fields. The steady-state photocurrent is obtained from the diagonal photon components of the expectation value of the time-dependent current operator outside the surface, while the off-diagonal terms of the expectation value of the current operator from both inside and outside the surface provide the probability of coherent emission of high-order harmonic radiation. It is found, among other things, that electrons can be emitted from the surface requiring no net absorption of photons or even accompanied by emission of extra photons. The origin of the effect lies in the difference in the ponderomotive energy inside and outside the surface that can arise from the small ratio of the effective mass of the electron inside the solid (e.g., GaAs) and the mass of the free electron. Another result of qualitative significance is the formation of a plateau, well known in the atomic case, in both the kinetic energy distribution of the photocurrent and the spectrum of the high-order harmonic radiation. They are shown to arise in the present case from the evanescent part of the electron wave function at the surface.

• OSTI ID: 20718168
• Journal Information: Physical Review. A, Vol. 72, Issue 2; Other Information: DOI: 10.1103/PhysRevA.72.023412; (c) 2005 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ABSORPTION
ALGORITHMS
CURRENTS
EFFECTIVE MASS
ELECTRONS
EXPECTATION VALUE
GALLIUM ARSENIDES
HARMONIC GENERATION
KINETIC ENERGY
LASER RADIATION
PHOTOCONDUCTIVITY
PHOTOEMISSION
PHOTONS
PONDEROMOTIVE FORCE
PROBABILITY
SEMICONDUCTOR MATERIALS
SOLIDS
SURFACES
TIME DEPENDENCE
WAVE FUNCTIONS