Research fueled by:

Freie Universitaet BerlinApril 12th, 2010

JAIRO SINOVATexas A&M University

Institute of Physics ASCR

New paradigms in spin-charge coupled physics in mutli-band systems

Hitachi CambridgeJoerg Wünderlich, A. Irvine, et al

Institute of Physics ASCRTomas Jungwirth, Vít Novák, et al

University of Würzburg Laurens Molenkamp, E. Hankiewiecz, et al

University of Nottingham Bryan Gallagher, Richard Campion, et al.

2Nanoelectronics, spintronics, and materials control by spin-orbit coupling

I. Introduction: using the dual personality of the electron•Electronics, ferromagnetism, and spintronics•Internal coupling of charge and spin: origin and present use

II. Control of material and transport properties through spin-orbit coupling:•Ferromagnetic semiconductors: magnetic anisotropy control•Anomalous Hall effect and spin-dependent Hall effects

• Spin injection Hall effect: a new paradigm in exploiting SO couplingSpin based FET: old and new paradigm in charge-spin transport

•Theory expectations and modeling•Experimental results•New experimental results, further checks, outlook

new paradigms in spin-charge coupled physics

new paradigms in spin-charge coupled physics

3Nanoelectronics, spintronics, and materials control by spin-orbit coupling

The electron: the key character with dual personalities

CHARGECHARGEEasy to manipulate: Coulomb interaction

SPIN 1/2SPIN 1/2Makes the electron antisocial: a fermion

quantum mechanics

E=p2/2mE→ iħ d/dtp→ -iħ d/dr

““Classical” external manipulation of charge & spinClassical” external manipulation of charge & spin

special relativity

E2/c2=p2+m2c2

(E=mc2 for p=0)

+ particles/antiparticles & spin

Dirac equation=

4Nanoelectronics, spintronics, and materials control by spin-orbit coupling

Using charge and spin in information technology

HIGH tunablity of electronic transportproperties the key to FET success in processing technology

substrate

semiconductor

insulatorS Dgate

Vg >0

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