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Updated: Jul 13, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum computers based on electron spins controlled by ultrafast off-resonant single optical pulses
Susan M Clark1, Kai-Mei C Fu, Thaddeus D Ladd
1Edward L. Ginzton Laboratory, Stanford University, Stanford, California 94305-4088, USA. sclark4@stanford.edu
Physical Review Letters
|August 7, 2007
Summary
We present a rapid quantum computing method using electron spins in quantum dots. This approach achieves high-fidelity quantum gates with fast operation times, paving the way for advanced quantum technologies.
Area of Science:
- Quantum Computing
- Quantum Information Science
- Solid-State Physics
Background:
- Quantum computers promise revolutionary computational power but face challenges in scalability and gate fidelity.
- Electron spins in quantum dots offer a promising platform for qubits due to their long coherence times and controllability.
- Integrating quantum dots with optical elements is crucial for efficient control and readout.
Purpose of the Study:
- To propose and theoretically demonstrate a fast and high-fidelity quantum computing architecture.
- To leverage optically controlled electron spins in quantum dots coupled to microcavities for quantum operations.
- To enable scalable quantum computation through nonlocal gate implementations.
Main Methods:
- Utilizing broadband optical pulses for electron spin manipulation and clocking.
- Implementing nonlocal two-qubit gates via phase shifts on laser pulses in a shared waveguide.
- Performing numerical simulations to assess gate fidelity and operation speed.
Main Results:
- Achieved high-fidelity single-qubit gates.
- Demonstrated high-fidelity two-qubit gates with nonlocal operations.
- Operation times were found to be comparable to the inverse Zeeman frequency, indicating high speed.
Conclusions:
- The proposed scheme offers a viable pathway towards fast and scalable quantum computation.
- Optically controlled electron spins in coupled quantum dots provide a robust platform for quantum information processing.
- This work contributes to the development of practical quantum computing architectures.
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