Effects of interactions in transport through Aharonov-Bohm-Casher interferometers

Kondo effect in transport through Aharonov-Bohm and Aharonov-Casher interferometers

We derive the extension of the Hubbard model to include Rashba spin-orbit coupling that correctly describes Aharonov-Bohm and Aharonov-Casher phases in a ring under applied magnetic and electric fields. When the ring is connected to conducting leads, we develop a formalism that is able to describe both, Kondo and interference effects. We find that in the Kondo regime, the spin-orbit coupling reduces strongly the conductance from the unitary limit. This effect in combination with the magnetic flux, can be used to produce spin polarized carriers.

Kondo Resonance in a Mesoscopic Ring Coupled to a Quantum Dot: Exact Results for the Aharonov-Bohm/Casher Effects

We study the persistent currents induced by both the Aharonov-Bohm and Aharonov-Casher effects in a one-dimensional mesoscopic ring coupled to a side-branch quantum dot at Kondo resonance. For privileged values of the Aharonov-Bohm-Casher fluxes, the problem can be mapped onto an integrable model, exactly solvable by a Bethe ansatz. In the case of a pure magnetic Aharonov-Bohm flux, we find that the presence of the quantum dot has no effect on the persistent current. In contrast, the Kondo resonance interferes with the spin-dependent Aharonov-Casher effect to induce a current which, in the str…

Kondo effect in a Aharonov-Casher interferometer

We consider a model describing a spin field-effect transistor based on a quantum nanowire with a tunable spin-orbit interaction embedded between two ferromagnetic leads with anticollinear magnetization. We investigate a regime of a strong interplay between resonance Kondo scattering and interference associated with the Aharonov-Casher effect. Using the Keldysh technique at weak coupling regime we calculate perturbatively the charge current. It is predicted that the effects of the spin-orbit interaction result in a non-vanishing current for any spin polarization of the leads including the case …

Aharonov-Casher Effect in Wigner Crystal Exchange Interactions

We theoretically study the effects of spin-orbit coupling on spin exchange in a low-density Wigner crystal. In addition to the familiar antiferromagnetic Heisenberg exchange, we find general anisotropic interactions in spin space if the exchange paths allowed by the crystal structure form loops in real space. In particular, it is shown that the two-electron exchange interaction can acquire ferromagnetic character.

扭曲双层石墨烯中的阿哈罗诺夫 - 卡什尔相位

Aharonov-Casher phase in twisted bilayer graphene

研究扭曲双层石墨烯中电子的阿哈罗诺夫 - 卡什尔相位，通过\(SU(2)\)矢量势确定相位并对哈密顿量规范变换，发现该相位与电场呈线性关系且在魔角处有尖锐峰值。

Spin selective transport through Aharonov-Bohm and Aharonov-Casher triple quantum dot systems

We calculate the conductance through a system of three quantum dots under two different sets of conditions that lead to spin filtering effects under an applied magnetic field. In one of them, a spin is localized in one quantum dot, as proposed by Delgado et al. [Phys. Rev. Lett. 101, 226810 (2008)]. In the other one, all dots are equivalent by symmetry and the system is subject to a Rashba spin-orbit coupling. We solve the problem using a simple effective Hamiltonian for the low-energy subspace, improving the accuracy of previous results. We obtain that correlation effects related to the Kondo…