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Updated: Sep 17, 2025
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
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Baseband control of single-electron silicon spin qubits in two dimensions
Florian K Unseld1, Brennan Undseth1, Eline Raymenants1
1QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, Delft, The Netherlands.
Nature Communications
|July 2, 2025
Summary
We demonstrate a new method for controlling quantum bits using hopping spins in silicon, achieving high fidelity comparable to existing techniques. This approach offers a promising path for scaling up quantum computing arrays.
Area of Science:
- Quantum Computing
- Solid-State Physics
- Materials Science
Background:
- Micromagnet-enabled electric-dipole spin resonance (EDSR) is a high-fidelity method for single-spin control in silicon, but limited to 1D arrays.
- Qubit control via hopping spins is an emerging alternative, showing high fidelity in 2D germanium arrays.
Purpose of the Study:
- To evaluate hopping spin control in a 2D silicon quantum dot array.
- To compare its fidelity and operational characteristics against EDSR.
- To propose a scalable design for future quantum computing architectures.
Main Methods:
- Fabrication and operation of a 2x2 28Si/SiGe quantum dot array.
- Implementation of both EDSR and baseband hopping spin control techniques.
- Fidelity measurements and analysis of operational parameters.
Main Results:
- Achieved a lower bound on hopping gate fidelity of 99.50(6)%, comparable to EDSR fidelity.
- Hopping control avoids the resonance shift and heating issues observed with EDSR.
- Proposed a scalable nanomagnet design for large-scale spin array control.
Conclusions:
- Hopping spin control is a viable and high-fidelity alternative to EDSR for silicon quantum dots.
- This method offers advantages in scalability and operational stability for quantum computing.
- The proposed nanomagnet design facilitates the advancement of large-scale silicon quantum computing arrays.
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