Anomalous magnetic response of a quasi-periodic mesoscopic ring in presence of Rashba and Dresselhaus spin-orbit interactions

Abstract

We investigate the properties of persistent charge current driven by magnetic flux in a quasiperiodic mesoscopic Fibonacci ring with Rashba and Dresselhaus spin-orbit interactions. Within a tight-binding framework we work out individual state currents together with net current based on second-quantized approach. A significant enhancement of current is observed in presence of spinorbit coupling and sometimes it becomes orders of magnitude higher compared to the spin-orbit interaction free Fibonacci ring. We also establish a scaling relation of persistent current with ring size, associated with the Fibonacci generation, from which one can directly estimate current for any arbitrary flux, even in presence of spin-orbit interaction, without doing numerical simulation. The present analysis indeed gives a unique opportunity of determining persistent current and has not been discussed so far.

Characteristics of persistent spin current components in a quasi-periodic Fibonacci ring with spin–orbit interactions: Prediction of spin–orbit coupling and on-site energy

“…The current exhibits an anomalous oscillation with SO coupling and its amplitude gradually decreases with increasing the coupling strength. This oscillation is characterized by the crossing of different distinct energy levels (viz, degeneracy) of the system, and also observed in other context 35,39 . The other feature i.e., the phase reversal of I z by interchang-ing the parameters α and β can be well understood from our previous analysis, and thus, the net Z-component of spin current should vanish under the situation α = β, which is not shown here to save space.…”

“…In addition, the earlier studies essentially focused on only one component (viz, Z-component), though it is extremely interesting and important too to study all three components of spin current to analyze spin dynamics of moving electrons in presence of SO fields. Motivated with this, in the present work we explore the behavior of persistent spin current in a one-dimensional (1D) quasi-periodic ring geometry where lattice sites are arranged in a Fibonacci sequence [37][38][39] , the simplest example of a quasi-periodic system. A Fibonacci chain is constructed by two basic units A and B following the specific rule A → AB and B → A.…”

Bias-induced circular spin current: Effects of environmental dephasing and disorder

“…To discuss spin dependent features, we need to include spin-dependent scattering effect 37,[47][48][49][50][51] in the system and that can be done in several ways. For instance, by con- sidering a magnetic quantum ring or by using a Rashba ring, or by some other ways.…”

Investigation of electronic properties of alloyed double metal ring

“…Most of the geometrical structures that studied are simple mesoscopic ring [3,[7][8][9][10], an array of mesoscopic rings [11], mesoscopic cylinder [12][13][14], Möbius strip [15]. In these studies, persistent currents have been calculated with respect to temperature [16,17], electron-phonon interaction [18], electron correlation [19], Rashba and Dresselhaus spin-orbit interactions [20,21] electric field [22].…”