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A Method for Evaluating Timeliness and Accuracy of Volitional Motor Responses to Vibrotactile Stimuli
Published on: August 2, 2016
Spin transistor action from hidden Onsager reciprocity.
İ Adagideli1, V Lutsker, M Scheid
1Faculty of Engineering and Natural Sciences, Sabanci University, Orhanli-Tuzla, Istanbul, Turkey.
Physical Review Letters
|September 26, 2012
Summary
We found that spin conductance vanishes in confined electrons with weak spin-orbit coupling. This spin current can be switched on or off by breaking time-reversal symmetry or adding transport terminals.
Area of Science:
- Condensed matter physics
- Quantum mechanics
- Spintronics
Background:
- Investigating electron behavior in confined systems with spin-orbit coupling is crucial for understanding quantum phenomena.
- Spin-orbit coupling influences electron spin and orbital motion, impacting electronic properties.
Purpose of the Study:
- To analyze generic Hamiltonians for confined electrons with weak inhomogeneous spin-orbit coupling.
- To understand the conditions under which spin conductance can be controlled.
Main Methods:
- Utilizing a local gauge transformation to simplify the SU(2) Hamiltonian structure to U(1)×U(1).
- Applying an Onsager relation to analyze spin conductance in a two-terminal setup.
- Performing numerical checks on mesoscopic cavities and Aharonov-Bohm rings.
Main Results:
- The SU(2) Hamiltonian structure reduces to U(1)×U(1) for spinless fermions in a fictitious orbital magnetic field.
- Spin conductance vanishes in a two-terminal setup under weak spin-orbit coupling.
- Spin conductance can be switched on by breaking time-reversal symmetry or adding transport terminals.
Conclusions:
- The study provides a theoretical framework for controlling spin currents in mesoscopic systems.
- The findings offer insights into the manipulation of spin transport, relevant for spintronic devices.
- The ability to switch spin current on/off presents opportunities for novel electronic applications.
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