Atom nanolithography with multilayer light masks: Particle optics analysis

Abstract

We study the focusing of atoms by multiple layers of standing light waves in the context of atom lithography. In particular, atomic localization by a double-layer light mask is examined using the optimal squeezing approach. Operation of the focusing setup is analyzed both in the paraxial approximation and in the regime of nonlinear spatial squeezing for the thin-thin as well as thinthick atom lens combinations. It is shown that the optimized double light mask may considerably reduce the imaging problems, improve the quality of focusing and enhance the contrast ratio of the deposited structures.

Atom lithography with near-resonant standing waves

“…1. Many aspects of atom focusing by the standing light waves can be explained in the semiclassical picture of the atom's interaction with the light induced potential [4,5,16]. Therefore, we start considering the problem in the classical framework.…”

“…II, the basic framework of the problem is defined and the focusing of atoms is studied classically under the influence of adiabatic light potentials. In this section, we examine the optimal squeezing scheme of [16] when applied to the atomic-beam traversing a near-resonant SW light. In Sec.…”

“…Most theoretical studies of atom lithography employ a particle optics approach to laser focusing of atoms [4,5,16]. The focal properties of the light have been examined in terms of time dependent classical trajectories of atoms in the light induced potential.…”

“…As a result, all current lithography schemes suffer from a considerable background in the deposited structures. A novel scheme to reduce the aberration problem was suggested recently in [16] by using optimized multilayer light masks. Quantum mechanical analysis of the focusing of atomic beams has been performed as well.…”

“…The parameters for the best focusing of atoms are found as functions of the detuning (|∆|) using the optimal squeezing method developed in Ref. [16]. To include momentum diffusion and spontaneous emission effects on atoms, we perform Monte Carlo wave function simulations.…”