Optical Signatures of the Tunable Band Gap and Valley-Spin Coupling in Silicene

Abstract

We investigate the optical response of the silicene and similar materials, such as germanene, in the presence of an electrically tunable band gap for variable doping. The interplay of spin orbit coupling, due to the buckled structure of these materials, and a perpendicular electric field gives rise to a rich variety of phases: a topological or quantum spin Hall insulator, a valley-spin-polarized metal and a band insulator. We show that the dynamical conductivity should reveal signatures of these different phases which would allow for their identification along with the determination of parameters such as the spin orbit energy gap. We find an interesting feature where the electric field tuning of the band gap might be used to switch on and off the Drude intraband response. Furthermore, in the presence of spin-valley coupling, the response to circularly polarized light as a function of frequency and electric field tuning of the band gap is examined. Using right- and left-handed circular polarization it is possible to select a particular combination of spin and valley index. The frequency for this effect can be varied by tuning the band gap.

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Cited by in corpus (62)

• Valley-Spin Polarization in the Magneto-Optical Response of Silicene and Other Similar 2D Crystals
• Magneto-Optical Conductivity of Silicene and Other Buckled Honeycomb Lattices
• Topological phase transitions in the photonic spin Hall effect
• Effect of electron-hole asymmetry on optical conductivity in 8-Pmmn borophene
• Dynamical Polarization Function, Plasmons and Screening in Silicene and Other Buckled Honeycomb Lattices
• Longitudinal and spin/valley Hall optical conductivity in single layer $Mo{S}_2$
• Optical Conductivity of Twisted Bilayer Graphene
• AC/DC Spin and Valley Hall Effects in Silicene and Germanene
• Optical Conductivity of Weyl Semimetals and Signatures of the Gapped Semimetal Phase Transition
• Direct Evidence of Interaction-Induced Dirac Cones in Monolayer Silicene/Ag(111) System
• Casimir Force Phase Transitions in the Graphene Family
• Spin and valley polarization of plasmons in silicene due to external fields
• Spin- and valley-dependent transport through arrays of ferromagnetic silicene junctions
• Magneto-optical conductivity in a topological insulator
• Optical properties of a semi-Dirac material
• Optical properties of massive anisotropic tilted Dirac systems
• Transport and optics at the node in a nodal loop semimetal
• Anisotropic longitudinal optical conductivities of tilted Dirac bands in 1T${}^{\prime }$-MoS${}_2$
• Electrically Engineered Band Gap in Two-Dimensional Ge, Sn, and Pb: A First-Principles and Tight-Binding Approach
• Valleytronics on the Surface of Topological Crystalline Insulator: Elliptic Dichroism and Valley-Selective Optical Pumping
• Magneto-optical transport properties of monolayer WSe2
• On the Optical Properties of Excitons in Buckled 2D Materials in an External Electric Field
• Strain-controlled valley and spin separation in silicene heterojunctions
• Direction dependent giant optical conductivity in 2D \textit{semi}-Dirac materials
• H-Si bonding-induced unusual electronic properties of silicene: a method to identify hydrogen concentration
• Topological quantum friction
• Infrared to terahertz optical conductivity of $n$-type and $p$-type monolayer MoS${}_2$ in the presence of Rashba spin-orbit coupling
• Identifying topological-band insulator transitions in silicene and other 2D gapped Dirac materials by means of Rényi-Wehrl entropy
• Dynamical optical conductivity for gapped $\alpha -{\mathcal{T}}_3$ materials with a curved "flat" band
• Landau levels and magnetic oscillations in gapped Dirac materials with intrinsic Rashba interaction
• Signatures of merging Dirac points in optics and transport
• Topological Phase Transitions and Quantum Hall Effect in the Graphene Family
• Phonon structure in dispersion curves and density of states of massive Dirac Fermions
• Signatures of Lifshitz transition in the optical conductivity of two-dimensional tilted Dirac materials
• Conductivity of Dirac fermions with phonon induced topological crossover
• Magnetic Properties of Dirac Fermions in a Buckled Honeycomb Lattice
• Detection of topological phase transitions through entropy measurements: the case of germanene
• The Haldane model under nonuniform strain
• Optical Conductivity of Topological Insulator Thin Films in a Quantizing Magnetic Field
• Entropic uncertainty relations and topological-band insulator transitions in 2D gapped Dirac materials
• Effects of parallel electric and magnetic fields on Rydberg excitons in buckled two-dimensional materials
• Broadband Transverse Electric Surface Wave in Silicene
• Probing topological phase transitions via quantum reflection in the graphene family materials
• Effects of spatial dimensionality and band tilting on the longitudinal optical conductivities in Dirac bands
• Biased doped silicene as a source for advanced electronics
• Entropy Signatures of Topological Phase Transitions
• Electron-phonon correlations on spin texture of gapped helical Dirac Fermions
• Low-temperature linear transport of two-dimensional massive Dirac fermions in silicene: residual conductivity and spin/valley Hall effects
• Drude weight and optical conductivity of a two-dimensional heavy-hole gas with $k$-cubic spin-orbit interactions
• Casimir forces in the flatland: interplay between photo-induced phase transitions and quantum Hall physics
• Faraday rotation and transmittance as markers of topological phase transitions in 2D materials
• Variable Coupling Strength of Silicene on Ag(111)
• Quantum revivals in HgTe/CdTe quantum wells and topological phase transitions
• Effects of electron-impurity scattering on density of states in silicene: impurity bands and band-gap narrowing
• Anomalous Transition Magnetic Moments in two-dimensional Dirac Materials
• Cyclotron Resonance in Topological Insulators: Non-Relativistic Effects
• Quantum Hall effect and optical magneto-conductivity of two-dimensional topological nodal-line semimetals
• Detection of topological states in two-dimensional Dirac systems by the dynamic spin susceptibility
• Vanishing of interband light absorption in a persistent spin helix state
• Optical spectrum of $n$-type and $p$-type monolayer MoS${}_2$ in the presence of proximity-induced interactions
• Emerging nonlinear Hall effect in Kane-Mele two-dimensional topological insulators
• Geometrical and electrical modulation on the transport property of silicene constrictions