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Production, detection, storage and release of spin currents
1Dipartimento di Fisica and Istituto Nazionale di Fisica Nucleare, Università di Roma Tor Vergata, Via della Ricerca Scientifica 1, I-00133 Rome, Italy.
Beilstein Journal of Nanotechnology
|March 31, 2015
Summary
Researchers demonstrate magnetic production of spin currents using quantum rings and magnetizable storage units. This method offers a novel alternative to optical and electric field techniques for generating spin currents.
Area of Science:
- Condensed Matter Physics
- Quantum Transport
Background:
- Quantum rings in ballistic circuits couple strongly to magnetic fields, especially when asymmetric.
- Properly connected rings can generate novel phenomena by pumping currents.
Purpose of the Study:
- To investigate the magnetic production of pure spin currents using quantum rings.
- To explore the use of magnetizable bodies as storage units for magnetization.
Main Methods:
- Utilizing a time-dependent magnetic field in the plane of a quantum ring at half filling.
- Employing numerical simulations to analyze magnetization storage and spin current generation.
Main Results:
- A pure spin current is pumped via spin-orbit interaction, excited by a time-dependent magnetic field.
- Magnetizable bodies act as storage units for magnetization, analogous to capacitors for charge.
- Generated spin currents exhibit oscillations during polarization exchange between storage units.
Conclusions:
- Magnetic production of spin currents provides a viable alternative to optical and electric field excitation methods.
- The developed technique offers a new pathway for controlling and utilizing spin currents.
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