Southwest Quantum Information and Technology

Quantum gas assembly using optical tweezers and neutral atom entanglement via local spin-exchange

Presenting Author: Mark Brown, University of Colorado at Boulder; JILA
Contributing Author(s): B. J. Lester, Y. Lin, A. M. Kaufman, M. Foss-Feig, M. L. Wall, A. M. Rey, and C. A. Regal

In our previous work we have built a robust set of tools for quantum gas assembly with neutral atoms in optical dipole traps. This includes the ability to rapidly and near-deterministically (91%) load single neutral atoms into arrays of tightly-focused optical dipole traps, perform trap-resolved imaging of the atoms, cool them to their motional ground state using Raman sideband cooling, perform atom tunneling via control of individual traps, and demonstrate the effect of quantum statistics on the dynamics of pure states via the atomic Hong-Ou-Mandel effect. Recently, we observed spin-exchange between two atoms placed in the same optical tweezer, an effect which enables the generation of spin-entanglement between the two atoms. Starting with two spatially separated atoms, we controllably apply a tunnel-coupling to load the atoms into the same optical tweezer but in distinct motional states. By initially preparing the atoms in opposing spin-states, contact interactions between the atoms along with their quantum statistics, yield the entangling dynamics. We experimentally verify that upon separating the atoms subsequent to these dynamics, the entanglement achieved prior is retained. Now we consider both a new way of adiabatically creating spin-entanglement and the prospect of simulating many-body physics in the Kondo Lattice Model. These techniques demonstrate a novel platform using mobile optical tweezers for assembly of uniform atom arrays for quantum-information applications.

Read this article online: http://www.nature.com/nature/journal/v527/n7577/full/nature16073.html, http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.115.073003, http://science.sciencemag.org/content/345/6194/306

(Session 5 : Thursday from 5:00 - 7:00 pm)