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Updated: May 11, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Polytype control of spin qubits in silicon carbide.
Abram L Falk1, Bob B Buckley, Greg Calusine
1Center for Spintronics and Quantum Computation, University of California, Santa Barbara, Santa Barbara, California 93106, USA.
Nature Communications
|May 9, 2013
Summary
Silicon carbide (SiC) polytypes host coherent, optically addressable defect spin states, including room-temperature quantum coherence. This discovery enables engineering of tailored spin qubits and networks for quantum information applications.
Area of Science:
- Quantum Information Science
- Materials Science
- Solid-State Physics
Background:
- Crystal defects are promising for solid-state quantum information.
- Research is expanding beyond nitrogen-vacancy centers in diamond to new spin systems.
- A materials-driven approach aims for 'designer' spins with tailored properties.
Purpose of the Study:
- To investigate silicon carbide (SiC) polytypes for coherent and optically addressable defect spin states.
- To explore the potential of crystal polymorphism in engineering spin qubits.
- To establish a route for creating dipole-coupled networks of addressable spins.
Main Methods:
- Investigated 4H, 6H, and 3C polytypes of SiC.
- Demonstrated coherent and optically addressable defect spin states.
- Utilized double electron-electron resonance (DEER) to measure spin interactions.
- Measured distinct optical and spin transition energies.
Main Results:
- All investigated SiC polytypes host coherent and optically addressable defect spin states.
- Quantum coherence was observed at room temperature in these SiC spin states.
- Long spin coherence times were achieved.
- Magnetic dipole interactions between spin ensembles in inequivalent lattice sites were measured.
Conclusions:
- Crystal polymorphism in SiC is a viable degree of freedom for engineering spin qubits.
- The identified defect spin states offer a route to dipole-coupled networks of separately addressable spins.
- This work expands the materials platform for quantum information technologies.
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