Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions

Abstract

We study ballistic transport of Dirac fermions in silicene through arrays of barriers, of width $d$, in the presence of an exchange field $M$ and a tunable potential of height $U$ or depth $-U$. The spin- and valley-resolved conductances as functions of $U$ or $M$, exhibit resonances away from the Dirac point (DP) and close to it a pronounced dip that becomes a gap when a critical electric field $E_z$ is applied. This gap widens by increasing the number of barriers and can be used to realize electric field-controlled switching of the current. The spin $p_s$ and valley $p_v$ polarizations of the current near the DP increase with $E_z$ or $M$ and can reach 100\% for certain of their values. These field ranges widen significantly by increasing the number of barriers. Also, $p_s$ and $p_v$ oscillate nearly periodically with the separation between barriers or wells and can be inverted by reversing $M$.

9 pages, 43 figures, to appear in PRB, figure resolutions reduced for size

References in corpus (8)

• Intrinsic and Rashba Spin-orbit Interactions in Graphene Sheets
• Valley-Polarized Metals and Quantum Anomalous Hall Effect in Silicene
• Electronic structure of silicon-based nanostructures
• Spin transport in proximity induced ferromagnetic graphene
• Coherent spin transport through a 350-micron-thick Silicon wafer
• Optical Signatures of the Tunable Band Gap and Valley-Spin Coupling in Silicene
• Realization of free-standing silicene using bilayer graphene
• Intrinsic spin Hall effect in silicene: transition from spin Hall to normal insulator

Cited by in corpus (17)

• Strain-controlled valley and spin separation in silicene heterojunctions
• Dirac Cone Pairs in Silicene Induced by Interface Si-Ag Hybridization: A First Principles Effective Band Study
• Controllable photo-induced spin and valley filtering in silicene
• Electron spin inversion in gated silicene nanoribbons
• Role of line defect in the bandgap and transport properties of silicene nanoribbons
• Electrostatic quantum dots in silicene
• Spin- and valley-dependent Goos-Hanchen effect in silicene and gapped graphene structures
• Photoenhanced spin/valley polarization and tunneling magnetoresistance in ferromagnetic-normal-ferromagnetic silicene junction
• Tunneling magnetoresistance and spin-valley polarization of aperiodic magnetic silicene superlattices
• Spin and valley manipulation in single and double electrostatic silicene quantum dots
• Electrical control of a confined electron spin in a silicene quantum dot
• Electron interferometry and quantum spin Hall phase in silicene
• Switching modulation of spin transport in ferromagnetic tetragonal silicene
• Photo-induced spin and valley-dependent Seebeck effect in the low-buckled Dirac materials
• Josephson effect in silicene-based SNS Josephson junction: Andreev reflection and free energy
• Geometrical and electrical modulation on the transport property of silicene constrictions
• Electric spin and valley Hall effects