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Updated: May 21, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Quantum information storage for over 180 s using donor spins in a 28Si "semiconductor vacuum"
M Steger1, K Saeedi, M L W Thewalt
1Department of Physics, Simon Fraser University, Burnaby, BC, Canada.
Science (New York, N.Y.)
|June 9, 2012
Summary
Researchers developed a new method using enriched silicon-28 to precisely control and measure nuclear spins. This breakthrough enables highly sensitive detection of phosphorus-31 nuclear magnetic resonance, achieving over 180 seconds of solid-state coherence time.
Area of Science:
- Quantum computing
- Solid-state physics
- Materials science
Background:
- Quantum computers need isolated, measurable systems with long coherence.
- Nuclear spins in solids offer long coherence but lack initialization and detection methods.
- Existing methods struggle with sensitivity and initializing nuclear spin states.
Purpose of the Study:
- To develop advanced techniques for initializing and reading out nuclear spin states in solids.
- To leverage the unique optical properties of enriched silicon-28 for quantum information processing.
- To achieve highly sensitive nuclear magnetic resonance detection at dilute concentrations.
Main Methods:
- Utilized hyperfine-resolved optical transitions in enriched silicon-28.
- Employed efficient Auger photoionization for nuclear hyperpolarization.
- Integrated optical transitions with electrical spin-readout for sensitive detection.
- Applied these techniques to detect dilute phosphorus-31 in silicon-28.
Main Results:
- Demonstrated rapid nuclear hyperpolarization and electrical spin-readout.
- Achieved highly sensitive nuclear magnetic resonance detection of dilute phosphorus-31.
- Measured a solid-state coherence time exceeding 180 seconds for nuclear spins.
- Enabled detection at concentrations previously inaccessible to conventional methods.
Conclusions:
- Enriched silicon-28's optical properties facilitate advanced nuclear spin control and readout.
- The developed techniques overcome major limitations in solid-state quantum information processing.
- This work paves the way for highly coherent solid-state quantum systems.
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