Individually controlled neutral atoms are quickly emerging as a leading platform for quantum science. Qubits with long coherence times can be encoded in spin states or, in the case of alkaline earth (-like) species, optical transitions involving a long-lived metastable state. Entangling operations are performed via interactions mediated by highly excited Rydberg states. However, several emerging directions in quantum science require the ability to precisely and programmably couple a subset of the system to the environment without decoding the remainder. For instance, quantum error correction requires measurement of stabilizers, and remote entanglement generation for quantum networking and distributed computing requires Bell state measurements of photons entangled with atoms. More fundamentally, “programmable openness” in quantum circuits may provide us with new insights on decoherence in many-body systems, as evidenced by the nascent notion of measurement-induced phase transitions.

We seek to add fast “mid-circuit measurements” and remote entanglement generation to the toolbox of programmable Rydberg atom arrays by leveraging the rich atomic structure of alkaline earth (-like) atoms. By encoding qubits in the nuclear spin-1/2 degree of freedom in the long-lived metastable state of ytterbium-171, we enable the ability to 1) perform “read enable” operations at will, and 2) perform remote entanglement generation over long fiber links by utilizing a strong optical transition in the telecommunications wavelength band. We will describe our progress in these directions and others based on two ytterbium-171 systems at UIUC where one features an optical cavity. We believe that this work will add “programmable openness” to the rapidly advancing Rydberg atom array platform, thereby unlocking a host of new directions.