| 1. |
- Misiorny, M., et al.
(författare)
-
Probing transverse magnetic anisotropy by electronic transport through a single-molecule magnet
- 2015
-
Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 91:3
-
Tidskriftsartikel (refereegranskat)abstract
- By means of electronic transport, we study the transverse magnetic anisotropy of an individual Fe-4 single-molecule magnet (SMM) embedded in a three-terminal junction. In particular, we determine in situ the transverse anisotropy of the molecule from the pronounced intensity modulations of the linear conductance, which are observed as a function of applied magnetic field. The proposed technique works at temperatures exceeding the energy scale of the tunnel splittings of the SMM. We deduce that the transverse anisotropy for a single Fe-4 molecule captured in a junction is substantially larger than the bulk value.
|
|
| 2. |
- Hell, M., et al.
(författare)
-
Spin resonance without spin splitting
- 2015
-
Ingår i: Physical Review B (Condensed Matter and Materials Physics). - 1098-0121. ; 91:19
-
Tidskriftsartikel (refereegranskat)abstract
- We predict that a single-level quantum dot without discernible splitting of its spin states develops a spin-precession resonance in charge transport when embedded into a spin valve. The resonance occurs in the generic situation of Coulomb blockaded transport with ferromagnetic leads whose polarizations deviate from perfect antiparallel alignment. The resonance appears when electrically tuning the interaction-induced exchange field perpendicular to one of the polarizations-a simple condition relying on vectors in contrast to usual resonance conditions associated with energy splittings. The spin resonance can be detected by stationary dI/dV spectroscopy and by oscillations in the time-averaged current using a gate-pulsing scheme. The generic noncollinearity of the ferromagnets and junction asymmetry allow for an all-electric determination of the spin-injection asymmetry, the anisotropy of spin relaxation, and the magnitude of the exchange field. We also investigate the impact of a nearby superconductor on the resonance position. Our simplistic model turns out to be generic for a broad class of coherent few-level quantum systems.
|
|
| 3. |
- Haupt, F., et al.
(författare)
-
Heat, molecular vibrations, and adiabatic driving in non-equilibrium transport through interacting quantum dots
- 2013
-
Ingår i: Physica Status Solidi. B: Basic Research. - : Wiley. - 0370-1972. ; 250:11, s. 2315-2329
-
Tidskriftsartikel (refereegranskat)abstract
- In this article we review aspects of charge and heat transport in interacting quantum dots and molecular junctions under stationary and time-dependent non-equilibrium conditions due to finite electrical and thermal bias. In particular, we discuss how a discrete level spectrum can be beneficial for thermoelectric applications, and investigate the detrimental effects of molecular vibrations on the efficiency of a molecular quantum dot as an energy converter. In addition, we consider the effects of a slow time-dependent modulation of applied voltages on the transport properties of a quantum dot and show how this can be used as a spectroscopic tool complementary to standard dc-measurements. Finally, we combine time-dependent driving with thermoelectrics in a double-quantum dot system -a nanoscale analog of a cyclic heat engine -and discuss its operation and the main limitations to its performance.
|
|
