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Updated: May 9, 2026
14:58
Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
Published on: June 3, 2015
Charge relaxation in a single-electron Si/SiGe double quantum dot.
K Wang1, C Payette, Y Dovzhenko
1Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
Physical Review Letters
|August 13, 2013
Summary
We measured the charge relaxation time of a single electron in a silicon quantum dot. This relaxation time, crucial for quantum computing, is tunable over four orders of magnitude.
Area of Science:
- Quantum Computing
- Solid-State Physics
- Semiconductor Nanostructures
Background:
- Quantum dots are essential for quantum computing.
- Understanding charge relaxation is key to qubit performance.
Purpose of the Study:
- To measure the interdot charge relaxation time (T1) of a single electron.
- To investigate the tunability of T1 in a Si/SiGe double quantum dot.
Main Methods:
- Utilized photon-assisted tunneling to determine the energy level structure.
- Systematically measured T1 as a function of detuning and interdot tunnel coupling.
Main Results:
- Identified a low-lying excited state in the charge qubit.
- Demonstrated that T1 is tunable over four orders of magnitude.
- Achieved a maximum T1 of 45 μs in the studied device.
Conclusions:
- The interdot charge relaxation time is highly tunable.
- This tunability is promising for developing robust quantum bits.
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