Non-dipole and relativistic effects in laser-atom interactions

Abstract

Descriptions of multiphoton phenomena based on the non-relativistic Schrodinger equation and the dipole approximation can break down at high laser intensities currently available. We first discuss how non-dipole effects, of order 1/c, due to the magnetic field component of a laser pulse, influence harmonic generation and atomic stabilization in the non-relativistic regime. Particular attention is devoted to photon emission by ions interacting with ultra-short, intense laser pulses. We then review progress in the theoretical study of relativistic effects arising when atoms interact with ultra-strong laser fields.