| 1. |
|
|
| 2. |
- Pertsova, Anna, et al.
(author)
-
Electrical control of spin dynamics in finite one-dimensional systems
- 2011
-
In: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X. ; 84, s. 155436-
-
Journal article (peer-reviewed)abstract
- We investigate the possibility of the electrical control of spin transfer in monoatomic chains incorporating spin impurities. Our theoretical framework is the mixed quantum-classical (Ehrenfest) description of the spin dynamics, in the spirit of thes-d model, where the itinerant electrons are described by a tight-binding model while localized spins are treated classically. Our main focus is on the dynamical exchange interaction between two well-separated spins. This can be quantified by the transfer of excitations in the form of transverse spin oscillations. We systematically study the effect of an electrostatic gate bias Vg on the interconnecting channel and we map out the long-range dynamical spin transfer as a function of Vg. We identify regions of Vg giving rise to significant amplification of the spin transmission at low frequencies and relate this to the electronic structure of the channel.
|
|
| 3. |
- Pertsova, Anna, et al.
(author)
-
Time-dependent electron transport through a strongly correlated quantum dot : multiple-probe open-boundary conditions approach
- 2013
-
In: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 25:10, s. 105501-
-
Journal article (peer-reviewed)abstract
- We present a time-dependent study of electron transport through a strongly correlated quantum dot, which combines adiabatic lattice density functional theory in the Bethe ansatz local-density approximation (BALDA) to the Hubbard model, with the multiple-probe battery method for open-boundary simulations in the time domain. In agreement with the recently proposed dynamical picture of Coulomb blockade, a characteristic driven regime, defined by regular current oscillations, is demonstrated for a certain range of bias voltages. We further investigate the effects of systematically improving the approximation for the electron–electron interaction at the dot site (going from non-interacting, through Hartree-only to adiabatic BALDA) on the transmission spectrum and the I–V characteristics. In particular, a negative differential conductance is obtained at large bias voltages and large Coulomb interaction strengths. This is attributed to the combined effect of the electron–electron interaction at the dot and the finite bandwidth of the electrodes.
|
|
