Image of the Week: simulating quantum spin models in microtraps

By Thomas Farrell on April 18, 2017

In a recent paper published in JPhysB, Shannon Whitlock et al propose a method of simulating lattice spin models based on “strong, long-range interacting Rydberg atoms stored in a large-spacing array of magnetic microtraps.” Current simulations of these models are usually performed computationally due to their complexity, due to quantum entanglement. Systems of ultracold atoms may be a useful alternative because the behaviour of the system could be controlled precisely. The image below shows how the excitation and readout could be achieved experimentally.

Proposed experimental setup for simulating quantum spin models in atomic ensembles confined in a microtrap array. Two spin states |↓〉 and |↑〉 are encoded in a single two-step excitation to the Rydberg state |n_↓S〉 or |n_↑S〉, shared amongst all atoms in an ensemble. The spatial extent of each ensemble is ℓ, the on-site blockade radius is r_c and the lattice spacing is a, with a ≳ r_c ≫ ℓ. The inset shows the internal level structure of a single atom with the states involved in the detection processes marked with dashed lines. General spin–spin interactions occur via long-range van der Waals interactions between the |n_↓S〉 and |n_↑S〉 states, from Shannon Whitlock et al 2017 J. Phys. B: At. Mol. Opt. Phys. 50 074001 © IOP Publishing, All Rights Reserved.