Engineering Zeeman-manifold quintets using state-dependent light shifts in neutral atoms

TL;DR

This paper introduces a method to engineer and control qudits in neutral atoms by combining Zeeman shifts and state-dependent light shifts, enabling high-fidelity manipulation of a five-level system for quantum computing.

Contribution

The authors demonstrate a novel approach to control Zeeman sublevels in neutral atoms for qudit encoding, with detailed numerical simulations showing high-fidelity operations.

Findings

State-preparation fidelity of ~0.99 within 1 microsecond

Single-qudit gate fidelity of ~0.99 with 2.5 microsecond pulses

Fast optical readout below 10 microseconds

Abstract

We present a general method for engineering qudits through individually addressable transitions between Zeeman sublevels, achieved by combining a large linear Zeeman shift with a state-dependent light shift. This approach lifts the degeneracy between adjacent states while simultaneously tuning their energy splittings into the radio-frequency (RF) domain, enabling coherent manipulation within the Zeeman manifold using experimentally accessible drive frequencies. As a concrete realization, we investigate the implementation of an $SU(5)$ \emph{quintet} encoded in the Zeeman sublevels of the long-lived $^3\mathrm{P}_2$ state of neutral $\mathrm{^{88}Sr}$ atoms confined in far-detuned, $\sigma^{-}$-polarized optical tweezers. Using realistic experimental parameters, we numerically demonstrate full control of the \emph{quintet} manifold, including initialization into a specific $SU(5)$ basis state via a multi-photon transfer, coherent state- and site-selective single-qudit rotations driven by RF fields, and fast state-selective optical readout. Our simulations predict state-preparation fidelities of $\mathcal{F} \simeq 0.99$ within $\sim 1~\mu \rm{s}$, single-qudit gate fidelities of $\mathcal{F} \simeq 0.99$ with $\pi$-pulse durations of $\sim 2.5~\mu \rm{s}$, and fast destructive imaging with durations below $10~\mu \rm{s}$. These results establish a broadly applicable framework for high-fidelity control of Zeeman sublevel-encoded qudits and highlight the $^3\mathrm{P}_2$ manifold in strontium as a promising platform for scalable qudit-based quantum technologies.