Effect of electron-hole asymmetry on optical conductivity in 8-Pmmn borophene

Abstract

We present a detail theoretical study of the Drude weight and optical conductivity of 8-$Pmmn$ borophene having tilted anisotropic Dirac cones. We provide exact analytical expressions of $xx$ and $yy$ components of the Drude weight as well as maximum optical conductivity. We also obtain exact analytical expressions of the minimum energy (${\epsilon }_1$) required to trigger the optical transitions and energy (${\epsilon }_2$) needed to attain maximum optical conductivity. We find that the Drude weight and optical conductivity are highly anisotropic as a consequence of the anisotropic Dirac cone. The optical conductivities have a nonmonotonic behavior with photon energy in the regime between ${\epsilon }_1$ and ${\epsilon }_2$, as a result of the tilted parameter $v_t$. The tilted parameter can be extracted by knowing ${\epsilon }_1$ and ${\epsilon }_2$ from optical measurements. The maximum values of the components of the optical conductivity do not depend on the carrier density and the tilted parameter. The product of the maximum values of the anisotropic conductivities has the universal value $(e^2/4\hslash {)}^2$. The tilted anisotropic Dirac cones in 8-$Pmmn$ borophene can be realized by the optical conductivity measurement.

6 pages, 3 figures, to appear in Physical Review B

References in corpus (7)

• Measurement of the Optical Conductivity of Graphene
• The optical conductivity of graphene in the visible region of the spectrum
• Tilted anisotropic Dirac cones in quinoid-type graphene and alpha-(BEDT-TTF)_2I_3
• Sum Rules for the Optical and Hall Conductivity in Graphene
• Electronic properties of 8-Pmmn borophene
• Strain-induced pseudomagnetic field in Dirac semimetal borophene
• Optical Signatures of the Tunable Band Gap and Valley-Spin Coupling in Silicene

Cited by in corpus (37)

• Signature of tilted Dirac cones in Weiss oscillations of $8-Pmmn$ borophene
• Optical properties of massive anisotropic tilted Dirac systems
• Anisotropic longitudinal optical conductivities of tilted Dirac bands in 1T${}^{\prime }$-MoS${}_2$
• Generalized WKB theory for electron tunneling in gapped $\alpha -{\mathcal{T}}_3$ lattices
• Optical absorption in two-dimensional materials with tilted Dirac cones
• Tunning the tilt of a Dirac cone by atomic manipulations: application to 8Pmmn borophene
• Dynamical band gap tuning in Weyl semi-metals by intense elliptically polarized normal illumination and its application to $8-Pmmn$ borophene
• Anomalous caustics and Veselago focusing in 8-Pmmn borophene p-n junctions with arbitrary junction directions
• Kubo conductivity for anisotropic tilted Dirac semimetals and its application to 8-Pmmn borophene: The role of different frequency, temperature and scattering limits
• Hyperbolic plasmons in massive tilted 2D Dirac materials
• Electrodynamics of tilted Dirac/Weyl materials: A unique platform for unusual surface plasmon polaritons
• Dynamical optical conductivity for gapped $\alpha -{\mathcal{T}}_3$ materials with a curved "flat" band
• Synthetic non-Abelian gauge fields and gravitomagnetic effects in tilted Dirac cone systems
• Valley-dependent time evolution of coherent electron states in tilted anisotropic Dirac materials
• Hyperbolic plasmon modes in tilted Dirac cone phases of borophene
• Valley caloritronics in a photodriven hetero-junction of Dirac materials
• Signatures of Lifshitz transition in the optical conductivity of two-dimensional tilted Dirac materials
• Floquet spectrum for anisotropic and tilted Dirac materials under linearly polarized light at all field intensities
• Electrically charged Andreev modes in two-dimensional tilted Dirac cone systems
• Dynamic polarization and plasmons in kekulé-patterned graphene: Signatures of the broken valley degeneracy
• Oblique and asymmetric Klein tunneling across smooth NP junctions or NPN junctions in 8-Pmmn borophene
• Mini Band Gap Generation in Magnetic Beta-Borophene: Effects of Optical Phonon Interaction
• Highly anisotropic optical conductivities in two-dimensional tilted semi-Dirac bands
• Effects of spatial dimensionality and band tilting on the longitudinal optical conductivities in Dirac bands
• Mapping borophene onto graphene: Quasi-exact solutions for guiding potentials in tilted Dirac cones
• Floquet spectrum and electronic transitions of tilted anisotropic Dirac materials under electromagnetic radiation: monodromy matrix approach
• Optical conductivity of tilted higher pseudospin Dirac-Weyl cones
• Thermal difference reflectivity of tilted 2D Dirac materials
• Time-diffraction and Zitterbewegung of two-dimensional massless Dirac excitations
• Strong anisotropic optical properties of 8-Pmmn borophene: a many-body perturbation study
• Tilted Dirac Cones in Two-Dimensional Materials: Impact on Electron Transmission and Pseudospin Dynamics
• Developing a semiclassical Wentzel-Kramers-Brillouin theory for $\alpha -{\mathcal{T}}_3$ model
• Designer gapped and tilted Dirac cones in lateral graphene superlattices
• Probing imbalanced Weyl nodes in two-dimensional anisotropic Weyl semimetal via optical conductivity
• Dirac materials under linear polarized light: quantum wave function evolution and topological Berry phases as classical charged particles trajectories under electromagnetic fields
• Excitonic instability in transition metal dichalcogenides
• Transport scaling and critical tilt effects in disordered two-dimensional Dirac fermions