Proposal for strong field physics simulation by means of optical waveguide

Abstract

Understanding the interaction of atoms and molecules with an intense laser radiation field is key for many applications such as high harmonic generation and attosecond physics. Because of the non-perturbative nature of strong field physics, some simplifications and approximation methods are often used to shed light on these processes. One of the most fruitful approaches to gain an insight into the physics of such interactions is the three-step-model, in which, the electron first tunnels out through the barrier and then propagates classically in the continuum. Despite the great success of this and other more sophisticated models there are still many ambiguities and open questions, e.g. how long it takes for the electron to tunnel through the barrier. Most of them stem from the difficulties in understanding electron trajectories in the classically ‘forbidden’ zone under the barrier. In this theoretical paper we show that strong field physics and the propagation of electromagnetic waves in a curved waveguide are governed by the same Schrödinger equation. We propose to fabricate a curved optical waveguide, and use this isomorphism to mimic strong field physics. Such a simulating system will allow us to directly probe the wave-function at any point, including the ‘tunneling’ zone.