Transport through single-level systems: Spin dynamics in the nonadiabatic regime
Abstract
We investigate the Fano-Anderson model coupled to a large ensemble of spins under the influence of an external magnetic field. The interaction between the two spin systems is treated within a mean-field approach, and we assume an anisotropic coupling between these two systems. By using a nonadiabatic approach, we make no further approximations in the theoretical description of our system, apart from the semiclassical treatment. Therewith, we can include the short-time dynamics as well as the broadening of the energy levels arising due to the coupling to the external electronic reservoirs. We study the spin dynamics in the regime of low and high bias. For the infinite bias case, we compare our results to those obtained from a simpler rate equation approach, where higher-order transitions are neglected. We show that these higher-order terms are important in the range of low magnetic field. Additionally, we analyze extensively the finite bias regime with methods from nonlinear dynamics, and we discuss the possibility of switching of the large spin.
- Publication:
-
Physical Review B
- Pub Date:
- December 2012
- DOI:
- 10.1103/PhysRevB.86.245317
- arXiv:
- arXiv:1208.4574
- Bibcode:
- 2012PhRvB..86x5317M
- Keywords:
-
- 75.76.+j;
- 85.75.-d;
- 73.63.Kv;
- 72.25.-b;
- Magnetoelectronics;
- spintronics: devices exploiting spin polarized transport or integrated magnetic fields;
- Quantum dots;
- Spin polarized transport;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 16 pages, 16 figures