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Demonstrating Experimentally the Encoding and Dynamics of an Error-Correctable Logical Qubit on a Hyperfine-Coupled
Sumin Lim1, Mikhail V Vaganov1, Junjie Liu1,2
1Department of Physics, University of Oxford, The Clarendon Laboratory, CAESR, Parks Road, Oxford OX1 3PU, United Kingdom.
Physical Review Letters
|March 7, 2025
Summary
High-dimensional quantum systems (qudits) offer efficient quantum error correction. We demonstrate a logical qubit using nuclear and electron spins, showing its potential for fault-tolerant quantum memories.
Area of Science:
- Quantum Information Science
- Quantum Computing Hardware
- Quantum Error Correction
Background:
- Scalable quantum computing requires effective quantum error correction.
- High-dimensional quantum systems (qudits) offer hardware-efficient alternatives to qubits.
- Electron-nuclear spin systems are promising platforms for quantum information processing.
Purpose of the Study:
- To implement and characterize a logical qubit using a four-level qudit.
- To investigate the protective capabilities of this encoding against magnetic field fluctuations.
- To assess the potential for fault-tolerant quantum memories.
Main Methods:
- Utilized electron-nuclear double resonance (ENDOR) techniques.
- Encoded a logical qubit onto the hyperfine-coupled electron-nuclear spin states (I=3/2 and S=1/2).
- Studied the dynamics of the encoded state under controlled magnetic field fluctuations and natural decoherence.
Main Results:
- Successfully implemented a logical qubit using a four-state qudit.
- Demonstrated protection against magnetic field fluctuations, a key decoherence source.
- Observed the dynamics of the encoded logical qubit under decoherence processes.
Conclusions:
- The demonstrated encoding provides inherent protection against dominant decoherence mechanisms.
- This approach shows significant potential for building practical, fault-tolerant quantum memories.
- High-dimensional qudit-based quantum error correction is a viable strategy for scalable quantum computing.
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