Suppressing errors is the central challenge for useful quantum computing^{1}, requiring quantum error correction (QEC)^{2–6}for largescale processing. However, the overhead in the realization of errorcorrected ‘logical’ qubits, in which information is encoded across many physical qubits for redundancy^{2–4}, poses substantial challenges to largescale logical quantum computing. Here we report the realization of a programmable quantum processor based on encoded logical qubits operating with up to 280 physical qubits. Using logicallevel control and a zoned architecture in reconfigurable neutralatom arrays^{7}, our system combines high twoqubit gate fidelities^{8}, arbitrary connectivity^{7,9}, as well as fully programmable singlequbit rotations and midcircuit readout^{10–15}. Operating this logical processor with various types of encoding, we demonstrate improvement of a twoqubit logic gate by scaling surfacecode^{6}distance from
 Award ID(s):
 1753240
 NSFPAR ID:
 10146601
 Date Published:
 Journal Name:
 Quantum
 Volume:
 3
 ISSN:
 2521327X
 Page Range / eLocation ID:
 180
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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