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Updated: Jul 10, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Coherent control of a single electron spin with electric fields
K C Nowack1, F H L Koppens, Yu V Nazarov
1Kavli Institute of Nanoscience, Delft University of Technology, Post Office Box 5046, 2600 GA Delft, the Netherlands. k.c.nowack@tudelft.nl
Science (New York, N.Y.)
|November 3, 2007
Summary
Researchers demonstrate electrical control of single-electron spins in quantum dots using electric fields. This breakthrough enables fast, coherent spin manipulation, paving the way for all-electrical control of spin qubits.
Area of Science:
- Quantum Information Science
- Condensed Matter Physics
- Quantum Computing
Background:
- Spin-based quantum information processing relies on precise spin manipulation.
- Electrical control is highly desirable for on-chip integration and scalability.
- Previous methods often relied on magnetic control, which is less practical for miniaturization.
Purpose of the Study:
- To experimentally achieve coherent control of a single-electron spin using electrical fields.
- To investigate the feasibility of all-electrical manipulation of spin qubits.
- To explore the underlying mechanisms of electrically induced spin transitions.
Main Methods:
- Utilizing an oscillating electric field generated by a local gate to control a single-electron spin in a quantum dot.
- Observing Rabi oscillations to quantify the speed and coherence of spin transitions.
- Analyzing the role of spin-orbit interaction in mediating electrical spin control.
Main Results:
- Demonstrated coherent control of a single-electron spin via an oscillating electric field.
- Achieved rapid spin rotations (90 degrees) in approximately 55 nanoseconds.
- Identified spin-orbit interaction as the key mechanism for electrically induced spin transitions.
Conclusions:
- Established the feasibility of fully electrical manipulation of spin qubits.
- Showcased rapid and coherent control of single spins using electric fields.
- This work is a significant step towards scalable, on-chip quantum information processing.
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