FYRIRLESTRAMARAÞON HR 2011 | RU LECTURE MARATHON 2011

Andrei Manolescu School of Science and Engineering

Spin currents in quantum rings

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WHAT IS SPIN

e

The electron rotates around the nucleus orbit

The electron rotates around itself spin magnetic dipole

e

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WHAT IS SPIN-ORBIT INTERACTION

The motion seen from the lab frame: The electron rotates around the nucleus

e e

The motion seen by the electron: The nucleus rotates around the electron and creates a magnetic field

In atoms

In crystals e

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WHAT IS SPINTRONICS

The electron has electric charge electric current Electronics: information carried by electric signals

The electron has spin magnetic (spin) current Spintronics: information carried by magnetic signals

The spin-orbit interaction allows the influence of electric fields on spin currents

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GaAs/AlGaAs heterostructure

Quantum ring Quantum wires

NANOELECTRONIC DEVICES

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TYPES OF SPIN-ORBIT INTERACTION IN NANOSTRUCTURES

Rashba: due to the electric field of the vertical confinement

Dresselhaus: due to the electric field of the crystal

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Charge currentSpin current

M. Niţă, D.C. Marinescu, A. Manolescu, V. Guðmundsson, Phys. Rev. B 2011

SPIN CURRENTS INDUCED IN NANORINGS

0Ring exposed to two dipolar electric fields with a relative angle 0

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SPIN INTERFERRENCE WITH R+D SOI

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THE NANOPHYSICS GROUP AT RU

Kristinn Torfason

Sigurdur Erlingsson Halldor Svavarsson Agust Valfells

Gunnar Thorgilsson

Andrei Manolescu

Anton Heidar Thorolfsson

Csaba Daday