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Updated: May 22, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Ultrafast quantum gates in circuit QED
G Romero1, D Ballester, Y M Wang
1Departamento de Química Física, Universidad del País Vasco UPV/EHU, Apartado 644, 48080 Bilbao, Spain.
Physical Review Letters
|May 1, 2012
Summary
We developed ultrafast quantum gates for circuit quantum electrodynamics, achieving high fidelity in ultrastrong coupling regimes. This breakthrough enables subnanosecond quantum operations, advancing quantum computing speed and accuracy.
Area of Science:
- Quantum Computing
- Quantum Information Science
- Quantum Electrodynamics
Background:
- Implementing high-fidelity quantum gates is crucial for scalable quantum computing.
- Ultrastrong coupling regimes in circuit quantum electrodynamics present unique challenges for gate implementation.
- Existing methods often struggle with speed and fidelity in these demanding regimes.
Purpose of the Study:
- To propose and validate a novel method for ultrafast two-qubit gates.
- To ensure the method's validity in ultrastrong and deep strong coupling regimes.
- To achieve high-fidelity quantum gates at subnanosecond timescales.
Main Methods:
- Utilizing state-of-the-art circuit quantum electrodynamics technology.
- Designing a specific qubit architecture.
- Implementing a four-step sequential displacement of the intracavity field.
- Performing ab initio calculations to verify performance.
Main Results:
- Demonstrated the feasibility of ultrafast two-qubit gates.
- Confirmed validity in ultrastrong and deep strong coupling regimes.
- Achieved gate operations at subnanosecond timescales.
- Maintained a fidelity exceeding 99%.
Conclusions:
- The proposed method enables efficient and high-fidelity quantum gate operations.
- This approach is suitable for advanced circuit quantum electrodynamics systems.
- The subnanosecond gate times represent a significant advancement for quantum computation speed.
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