Signatures of atomic structure in subfemtosecond laser-driven electron dynamics in nanogaps

Abstract

Coupled Maxwell and quantum-mechanical equations are used to simulate the electron dynamics in nanogaps in systems containing thousands of atoms. It will be shown that besides the carrier-envelop phase, bow-tie or gap shape, and gap size, the atomistic structure also significantly alters the electron dynamics. Atomic-scale interference fringes appear not only in the electron density but in the electron current and field enhancement as well. Electron bursts emerge from individual atoms and scatter on atoms driven by the direction of the laser. The time-dependent orbital-free density functional theory coupled to the Maxwell equations allows us to simulate physical systems approaching the realistic size and to explore the physical mechanism controlling the electron dynamics.