Spintromechanical Aspects of Charge Transport in Nanostructures
Examensarbete för masterexamen
Applied physics (MPAPP), MSc
Coupling between electronic and mechanical degrees of freedom caused by electronic spin, rather than by electronic charge is considered for magnetic nanoelectro-mechanical device. Such coupling makes it possible to achieve a mechanical displacement of the movable dot differently for diffrent orientations of spin of an electron being injected (spin-polaronic state). A giant spin-dependent tunneling, caused by spin-selective trans-mission of electrons through spin-polaronic states is predicted for finite temperatures and voltages up to characteristic correlation energy flint, set by a sum of polaronic and Coulomb blockade energies. This allows for electrically controlled spintromechanics by means of driving and gate voltages. The later is demonstrated by prediction of phenomenon of Coulomb promotion of single electron spintromechanical tunneling. Thermally activated nanomechanical vibration of the shuttle position allows for exponential temperature dependence of the current at voltages exceeding the correlation energy flint. For realistic device parameters the spin polarization of tunneling electrons can be achieved more than 99%.
Fysik , Physical Sciences