Interspecies Förster resonances for Rb-Cs Rydberg d-states for enhanced multi-qubit gate fidelities

Abstract

We present an analysis of interspecies interactions between Rydberg d-states of rubidium and cesium. We identify the Förster resonance channels offering the strongest interspecies couplings, demonstrating the viability for performing high-fidelity two- and multi-qubit C_{k}Z gates up to k=4, including accounting for blockade errors evaluated via numerical diagonalization of the pair potentials. Our results show d-state orbitals offer enhanced suppression of intraspecies couplings compared to s-states, making them well suited for use in large-scale neutral atom quantum processors.