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All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
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Donor-driven spin relaxation in multivalley semiconductors
Yang Song1, Oleg Chalaev1, Hanan Dery2
1Department of Electrical and Computer Engineering, University of Rochester, Rochester, New York 14627, USA.
Physical Review Letters
|November 1, 2014
Summary
Donor atom identity impacts spin relaxation in silicon, a puzzle for spintronics. Our theory explains this via impurity scattering and valley transfer, offering guidelines to enhance spin lifetime in devices.
Area of Science:
- Condensed matter physics
- Materials science
- Quantum mechanics
Background:
- Spin relaxation dependence on donor atom identity in n-type silicon is unexplained.
- This poses a long-standing challenge for semiconductor spintronics.
Purpose of the Study:
- To explain the observed dependence of spin relaxation on donor atom identity in n-type silicon.
- To provide theoretical insights for enhancing spin lifetime in spintronics devices.
Main Methods:
- Multivalley theory of conduction bands in silicon and germanium.
- Analysis of short-range scattering off central-cell impurity potentials.
- Symmetry arguments to determine spin-flip process impact.
Main Results:
- Spin-flip amplitude is dominated by short-range scattering off the central-cell potential.
- Electron transfer to a different k-space valley axis after scattering is key.
- This spin-flip process significantly affects spin relaxation in multivalley materials.
Conclusions:
- The developed theory explains the donor-dependent spin relaxation.
- Provides physical insights and guidelines to enhance spin lifetime.
- Offers a pathway for advancing semiconductor spintronics technology.
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