Quantum error correction of spin quantum memories in diamond under a zero magnetic field.

Nakazato, Takaya; Reyes, Raustin; Imaike, Nobuaki; Matsuda, Kazuyasu; Tsurumoto, Kazuya; Sekiguchi, Yuhei; Kosaka, Hideo

Fault-tolerant quantum memory plays a key role in interfacing quantum computers with quantum networks to construct quantum computer networks. Manipulation of spin quantum memory generally requires a magnetic field, which hinders the integration with superconducting qubits. Completely zero-field operation is desirable for scaling up a quantum computer based on superconducting qubits. Here we demonstrate quantum error correction to protect the nuclear spin of the nitrogen as a quantum memory in a diamond nitrogen-vacancy center with two nuclear spins of the surrounding carbon isotopes under a zero magnetic field. The quantum error correction makes quantum memory resilient against operational or environmental errors without the need for magnetic fields and opens a way toward distributed quantum computation and a quantum internet with memory-based quantum interfaces or quantum repeaters. The efficacy of quantum error correction of spins in a diamond nitrogen-vacancy that uses magnetic fields depends on spin's location in the lattice. Here, an alternative, zero-field approach relying on geometric phase is demonstrated in a three-qubit system.

MAGNETIC fields; QUANTUM computing; NUCLEAR spin; GEOMETRIC quantum phases; COMPUTER interfaces; QUANTUM computers; COMPUTER networks

Communications Physics, 2022, Vol 5, Issue 1, p1

2399-3650

Academic Journal

10.1038/s42005-022-00875-6