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Quantum dissipative Rashba spin ratchets
Sergey Smirnov1, Dario Bercioux, Milena Grifoni
1Institut für Theoretische Physik, Universität Regensburg, Regensburg, Germany.
Physical Review Letters
|July 23, 2008
Summary
This study demonstrates generating a spin current using unbiased AC power in asymmetric structures with spin-orbit interaction. Strong dissipation does not hinder equilibrium spin currents, revealing pure spin ratchet behavior.
Area of Science:
- Condensed matter physics
- Quantum mechanics
Background:
- Spin currents are crucial for spintronic devices.
- Understanding electron dynamics in low-dimensional systems is essential.
- Rashba spin-orbit interaction influences electron spin behavior.
Purpose of the Study:
- To predict the generation of a finite stationary spin current.
- To investigate pure spin ratchet behavior in asymmetric structures.
- To analyze the effect of strong dissipation on spin currents.
Main Methods:
- Theoretical prediction of spin current generation.
- Analysis of electron dynamics under unbiased AC driving.
- Modeling quasi-one-dimensional asymmetric periodic structures with Rashba spin-orbit interaction and strong dissipation.
Main Results:
- A finite stationary spin current can be generated.
- Pure spin ratchet behavior (spin current without charge transport) observed.
- Strong dissipation does not destroy equilibrium spin currents.
Conclusions:
- Unbiased AC driving can induce spin currents in specific asymmetric structures.
- Pure spin ratchet effect is achievable even with strong dissipation.
- The findings have implications for designing novel spintronic devices.
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