Lorentz force effects for graphene Aharonov-Bohm interferometers

Abstract

We investigate magnetic deflection of currents that flow across the Aharonov-Bohm interferometers defined in graphene. We consider devices induced by closed n-p junctions in nanoribbons as well as etched quantum rings. The deflection effects on conductance are strictly correlated with the properties of the ring-localized quasibound states. The energy of these states, their lifetime and the periodicity of the conductance oscillations are determined by orientation of the current circulating within the interferometer. Formation of high harmonics of conductance at high magnetic field and the role of intervalley scattering are discussed.

Electron spin inversion in fluorinated graphene nanoribbons

“…This results from an increasing magnetic confinement of the currents near the edge and the junction which decreases the coupling between the edge currents and the circular junction currents [ Fig. 2] [44,45]. The effect results in reduction of the coupling of the n-p junction to the edge.…”

“…3. The quantum ring [45] supports localized resonances with the current circulation of a fixed orientation. The results for the ring attached to the thin ribbon with the Zeeman interaction is given in Fig.…”

“…for the magnetic field oriented in the +z direction which injects [45,51] the incident electron wave function from the ribbon to the quantum ring. The injection occurs only provided that a localized resonance is supported by the ring for the applied value of the magnetic field [45]. For strong magnetic field oriented in the −z direction, the electron wave function is kept to the lower edge of the ribbon and does not notice the presence of the ring.…”

“…The resulting spin precession is stable against the spin Zeeman interaction. Quantum rings are defined in graphene ribbons with a well established by etching techniques [47][48][49][50][51] and the role o the magnetic focusing has been discussed recently [45,51].…”

Understanding magnetic focusing in graphene p−n junctions through quantum modeling

“…Spatially resolved particle current density maps have been useful in the past for understanding transport in graphene subjected to a magnetic field [46].…”