Fresnel zone plates for reconfigurable atomic waveguides

TL;DR

This paper introduces a scalable, reconfigurable Fresnel zone plate design that combines static diffraction-limited focusing with dynamic control, enabling versatile atomic waveguides for quantum applications.

Contribution

It presents a new FZP design compatible with SLMs, allowing dynamic reconfiguration of atomic waveguides with high resolution and large area scalability.

Findings

Enables dynamic generation of rings, arcs, and lattices.

Provides a scalable FZP design compatible with SLMs.

Facilitates smooth, adaptable atomic waveguides for interferometry.

Abstract

Fresnel zone plates (FZPs), with patterns of $1\,\mu$m resolution, allow the formation of clean, diffraction-limited foci -- but have a static phase profile. Spatial light modulators (SLMs) allow dynamic control of spatial beam intensity and phase -- but are bulky and currently limited to roughly $10\,\mu$m pixel sizes and $1\,$Mega-pixel formats. Here, we present a new `best-of-both' kind of FZP, scalable to large area rings currently incompatible with direct SLM generation. It is equivalent to a plano-convex donut lens, whereby light's local intensity and global phase at the FZP map directly onto the image plane. The same FZP under different SLM illumination can generate: rings and arcs, double-rings, phase windings and ring lattices (or dynamic combinations thereof). The smooth and adaptable near-field waveguide this enables will be ideal for Sagnac interferometry with ultracold atoms.