Single-site addressing of ultracold atoms beyond the diffraction limit via position dependent adiabatic passage

TL;DR

This paper introduces a novel single-site addressing method for ultracold atoms using the SLAP technique, achieving sub-wavelength resolution beyond the diffraction limit with high robustness and efficiency.

Contribution

The authors present a new approach employing adiabatic passage with a spatially structured pump field to selectively address individual atoms in an optical lattice, surpassing previous resolution limits.

Findings

Achieves spatial resolution better than the diffraction limit.

Demonstrates robustness against parameter variations.

Provides analytic and numerical validation for Rb-87 atoms.

Abstract

We propose a single-site addressing implementation based on the sub-wavelength localization via adiabatic passage (SLAP) technique. We consider a sample of ultracold neutral atoms loaded into a two-dimensional optical lattice with one atom per site. Each atom is modeled by a three-level \Lambda-system in interaction with a pump and a Stokes laser pulse. Using a pump field with a node in its spatial profile, the atoms at all sites are transferred from one ground state of the system to the other via stimulated Raman adiabatic passage, except the one at the position of the node that remains in the initial ground state. This technique allows for the preparation, manipulation, and detection of atoms with a spatial resolution better than the diffraction limit, which either relaxes the requirements on the optical setup used or extends the achievable spatial resolution to lattice spacings smaller than accessible to date. In comparison to techniques based on coherent population trapping, SLAP gives a higher addressing resolution and has additional advantages such as robustness against parameter variations, coherence of the transfer process, and the absence of photon induced recoil. Additionally, the advantages of our proposal with respect to adiabatic spin-flip techniques are highlighted. Analytic expressions for the achievable addressing resolution and efficiency are derived and compared to numerical simulations for Rb-87 atoms in state-of-the-art optical lattices.