Large spin-orbit effects in small quantum dots
arXiv:cond-mat/0609460 · doi:10.1103/PhysRevB.75.075327
Abstract
We consider small ballistic quantum dots weakly coupled to the leads in the chaotic regime and look for significant spin-orbit effects. We find that these effects can become quite prominent in the vicinity of degeneracies of many-body energies. We illustrate the idea by considering a case where the intrinsic exchange term -JS^2 brings singlet and triplet many-body states near each other, while an externally tunable Zeeman term then closes the gap between the singlet and the one of the triplet states (with spin projection parallel the external field). Near this degeneracy, the spin-orbit coupling leads to a striking temperature dependence of the conductance, with observable effects of order unity at temperatures lower than the strength of the spin-orbit coupling. Under favorable circumstances, spelled out in the paper, these order unity effects in the conductance persist to temperatures much higher than the spin-orbit coupling strength. Our conclusions are unaffected by the presence of non-universal perturbations. We suggest a class of experiments to explore this regime.
13 pages, 8 figures
References in corpus (11)
- Spin and Polarized Current from Coulomb Blockaded Quantum Dots
- Spin-orbit coupling and anisotropy of spin splitting in quantum dots
- Weak localization and conductance fluctuations in a quantum dot with parallel magnetic field and spin-orbit scattering
- Anisotropy of spin splitting and spin relaxation in lateral quantum dots
- Spin-orbit interaction in quantum dots in the presence of exchange correlations
- Orbital Effects of In-Plane Magnetic Fields Probed by Mesoscopic Conductance Fluctuations
- Electron correlations in metal nanoparticles with spin-orbit scattering
- Conductance Fluctuations and Spin Symmetries in Quantum Dots
- Fluctuations of g-factors in metal nanoparticles: Effects of electron-electron interaction and spin-orbit scattering
- Random Matrix Crossovers and Quantum Critical Crossovers for Interacting Electrons in Quantum Dots
- Antilocalization in Coulomb Blockade