Fast measurements and multiqubit gates in dual-species atomic arrays

Abstract

We propose and analyze an approach for fast syndrome measurements in an array of rubidium and cesium atomic qubits. The scheme works by implementing an interspecies controlled-not (cnot${}_{k}$) gate, entangling one cesium ancilla qubit with $k\ensuremath{\ge}1$ rubidium qubits which are then used for state measurement. Utilizing Rydberg states with different interspecies and intraspecies interaction strengths, the proposal provides a syndrome measurement fidelity of $\mathcal{F}>0.9999$ in less than $5\phantom{\rule{0.28em}{0ex}}\textmu{}\mathrm{s}$ of integration time.