Petr Seba

Quantum vortices in mezoscopic transport

We consider resonant vortices around nodal points of the wavefunction in an electron transport through a mesoscopic device. With a suitable choice of the device geometry, a dominating role is played by single vortices of a preferred orientation. To characterize their strength and resulting magnetic moment we introduce a magnetance, a quantity defined in analogy with the device conductance. Its basic properties and possible experimental detection will be discussed. In the case of a electron transport through material with spin-orbit interaction the existence of vortices and of the related magnetic moment can lead to the existence of Hall voltage. We will demonstrate this phenomena by numerical and symmetrical considerations. We show that for a cross junction this leads finally to a spin polarization of left/ right outgoing electrons although incident electrons were unpolarized. Moreover a transmission of spin polarized electrons leads to the appearance of Hall voltage also in the case when the external magnetic field equals to zero.