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Updated: May 30, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Charge-state conditional operation of a spin qubit.
I van Weperen1, B D Armstrong, E A Laird
1Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Physical Review Letters
|August 16, 2011
Summary
We demonstrate coherent control of a singlet-triplet qubit using an adjacent double quantum dot. This four-dot system enables fast conditional gate operations for two-qubit logic, advancing singlet-triplet spin qubit development.
Area of Science:
- Quantum Computing
- Solid-State Physics
- Quantum Information Science
Background:
- Singlet-triplet qubits are promising candidates for quantum computation.
- Efficient control mechanisms are crucial for scaling quantum processors.
- Two-qubit gates are essential for building universal quantum computers.
Purpose of the Study:
- To demonstrate coherent operation of a singlet-triplet qubit.
- To investigate the use of an adjacent double quantum dot for qubit control.
- To enable fast conditional gate operations for two-qubit logic.
Main Methods:
- Utilizing a four-dot system with electrostatically coupled quantum dots.
- Controlling a singlet-triplet qubit via electron spatial arrangement.
- Extracting capacitive coupling strength between qubit and control dots.
Main Results:
- Achieved coherent operation of the singlet-triplet qubit.
- Demonstrated fast conditional gate operation using the specific four-dot geometry.
- Quantified the capacitive coupling, confirming its suitability for gate operations.
Conclusions:
- The reported device geometry facilitates efficient two-qubit operations.
- This work paves the way for implementing a universal set of gates for singlet-triplet spin qubits.
- Advances in qubit control are critical for the realization of scalable quantum computers.
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