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Updated: Jul 7, 2026
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
Fault-tolerant linear optical quantum computing with small-amplitude coherent States
A P Lund1, T C Ralph, H L Haselgrove
1Centre for Quantum Computer Technology, Department of Physics, University of Queensland, St. Lucia, QLD 4072, Australia. lund@physics.uq.edu.au
Physical Review Letters
|February 1, 2008
Summary
Quantum computing with coherent states is feasible for fault tolerance, requiring only small amplitudes (alpha>1.2) when using error correction. This approach offers significantly lower resource overheads compared to single-photon schemes.
Area of Science:
- Quantum Information Science
- Quantum Computing Architectures
- Quantum Error Correction
Background:
- Coherent state qubits offer a promising alternative for quantum computing due to potentially lower overheads.
- Concerns exist regarding the practical implementation due to the fragility of diagonal states with large coherent amplitudes.
Purpose of the Study:
- To investigate the feasibility of fault-tolerant quantum computing using coherent states.
- To determine the minimum amplitude requirements for fault tolerance in this architecture.
- To compare resource overheads with existing quantum computing schemes.
Main Methods:
- Utilized Monte Carlo simulations to study fault tolerance.
- Analyzed the impact of small amplitudes and photon loss on qubit stability.
- Evaluated resource requirements for encoding qubits.
Main Results:
- Demonstrated that fault-tolerant quantum computing is achievable with small coherent state amplitudes (alpha > 1.2) when employing error correction.
- Identified significantly lower resource overheads at the first encoding level compared to leading single-photon schemes.
Conclusions:
- Coherent state qubits are a viable basis for fault-tolerant quantum computing.
- Error correction effectively mitigates fragility issues associated with larger amplitudes.
- This architecture presents a substantial advantage in resource efficiency.
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