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Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Quantum readout and fast initialization of nuclear spin qubits with electric currents
Noah Stemeroff1, Rogério de Sousa
1Department of Physics and Astronomy, University of Victoria, Victoria, British Columbia V8W 3P6, Canada.
Physical Review Letters
|December 21, 2011
Summary
We developed a theory for using electric currents to control nuclear spin qubits in semiconductors. This enables sensitive quantum detection and fast initialization for these long-lasting qubits.
Area of Science:
- Quantum computing
- Solid-state physics
- Materials science
Background:
- Nuclear spin qubits offer long coherence times, crucial for quantum computation.
- Efficient quantum readout and initialization remain significant challenges for solid-state qubits.
Purpose of the Study:
- To present a theoretical framework for the interaction between electric currents and nuclear spins in semiconductor donor impurities.
- To establish a sensitivity criterion for quantum detection of nuclear spin states.
- To propose an all-electrical method for rapid nuclear spin qubit initialization.
Main Methods:
- Theoretical modeling of electric current interaction with nuclear spins.
- Analysis of electrically detected magnetic resonance (EDMR) for quantum state detection.
- Development of an electrical protocol for qubit initialization.
Main Results:
- A sensitivity criterion for quantum detection of nuclear spin states via EDMR was derived.
- An all-electrical method for fast nuclear spin qubit initialization was proposed.
Conclusions:
- The developed theory provides a pathway for overcoming key challenges in nuclear spin qubit control.
- This work advances the potential of solid-state nuclear spins for practical quantum computing applications.
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