Coherent coupling and non-destructive measurement of trapped-ion mechanical oscillators

authored by

Pan Yu Hou, Jenny J. Wu, Stephen D. Erickson, Daniel C. Cole, Giorgio Zarantonello, Adam D. Brandt, Shawn Geller, Alex Kwiatkowski, Scott Glancy, Emanuel Knill, Andrew C. Wilson, Daniel H. Slichter, Dietrich Leibfried

Abstract

Precise quantum control and measurement of several harmonic oscillators, such as the modes of the electromagnetic field in a cavity or of mechanical motion, are key for their use as quantum platforms. The motional modes of trapped ions can be individually controlled and have good coherence properties. However, achieving high-fidelity two-mode operations and non-destructive measurements of the motional state has been challenging. Here we demonstrate the coherent exchange of single motional quanta between spectrally separated harmonic motional modes of a trapped-ion crystal. The timing, strength, and phase of the coupling are controlled through an oscillating electric potential with suitable spatial variation. Coupling rates that are much larger than decoherence rates enable demonstrations of high-fidelity quantum state transfer and beam-splitter operations, entanglement of motional modes, and Hong–Ou–Mandel-type interference. Additionally, we use the motional coupling to enable repeated non-destructive projective measurement of a trapped-ion motional state. Our work enhances the suitability of trapped-ion motion for continuous-variable quantum computing and error correction and may provide opportunities to improve the performance of motional cooling and motion-mediated entangling interactions.

Organisation(s)

Institute of Quantum Optics

External Organisation(s)

National Institute of Standards and Technology (NIST)
University of Colorado Boulder
Tsinghua University
Quantinuum
ColdQuanta, Inc.
QUDORA Technologies GmbH

Type

Article

Journal

Nature physics

Volume

20

Pages

1636-1641

No. of pages

6

ISSN

1745-2473

Publication date

10.2024

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Physics and Astronomy

Electronic version(s)

https://doi.org/10.48550/arXiv.2205.14841 (Access: Open)
https://doi.org/10.1038/s41567-024-02585-y (Access: Closed)