Electronic states of SnTe and PbTe (001) monolayers with supports

Kobayashi, Katsuyoshi

doi:10.1016/j.susc.2015.04.009

Cited by 12 publications

(13 citation statements)

References 36 publications

(46 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lattice vectors are relaxed until the stress is less than 0.01 GPa. Our firstprinciples calculations show that the buckled phase of the PbX monolayer is more stable than the centrosymmetric planar phase 8 , consistent with other DFT studies 16,48 . Detailed discussions on the bistable nature, ferroelectric properties and orbital-spin texture properties of lead chalcogenides can be found in our previous paper 8 .…”

Section: Discussionsupporting

confidence: 90%

Strain-induced gauge and Rashba fields in ferroelectric Rashba lead chalcogenide PbX monolayers ( X=S , Se, Te)

et al. 2018

View full text Add to dashboard Cite

One of the exciting features of two-dimensional (2D) materials is their electronic and optical tunability through strain engineering. Previously we found a new class of 2D ferroelectric Rashba semiconductors PbX (X=S, Se, Te) with tunable spin-orbital properties. In this work, based on our previous tight-binding (TB) results, we derive an effective low-energy Hamiltonian around the symmetry points that captures the effects of strain on the electronic properties of PbX. We find that strains induce gauge fields which shift the Rashba point and modify the Rashba parameter. This effect is equivalent to the application of in-plane magnetic fields. The out-of-plane strain, which is proportional to the electric polarization, is also shown to modify the Rashba parameter. Overall, our theory connects strain and spin-splitting in ferroelectric Rashba materials, which will be important to understand the strain-induced variations in local Rashba parameters that will occur in practical applications.

show abstract

Section: Discussionsupporting

confidence: 90%

Strain-induced gauge and Rashba fields in ferroelectric Rashba lead chalcogenide PbX monolayers ( X=S , Se, Te)

et al. 2018

View full text Add to dashboard Cite

show abstract

“…A number of theoretical studies of the physical properties of some two-dimensional group-IV tellurides have been published [ 45 , 46 , 47 , 48 ]; however, a systematic investigation of the effect of the anisotropic structure on the electronic and optical properties of monolayer group-IV tellurides is still lacking. In this paper, we systematically study the quasiparticle band structures and optical properties of group-IV tellurides (SiTe, GeTe, SnTe, PbTe) by means of predictive calculations based on the accurate many-body perturbation GW theory and the Bethe–Salpeter equation.…”

Section: Introductionmentioning

confidence: 99%

Anisotropic to Isotropic Transition in Monolayer Group-IV Tellurides

Wang

Urban

et al. 2021

Materials

View full text Add to dashboard Cite

Monolayer group-IV tellurides with phosphorene-derived structures are attracting increasing research interest because of their unique properties. Here, we systematically studied the quasiparticle electronic and optical properties of two-dimensional group-IV tellurides (SiTe, GeTe, SnTe, PbTe) using the GW and Bethe–Salpeter equation method. The calculations revealed that all group-IV tellurides are indirect bandgap semiconductors except for monolayer PbTe with a direct gap of 1.742 eV, while all of them are predicted to have prominent carrier transport ability. We further found that the excitonic effect has a significant impact on the optical properties for monolayer group-IV tellurides, and the predicted exciton binding energy is up to 0.598 eV for SiTe. Interestingly, the physical properties of monolayer group-IV tellurides were subject to an increasingly isotropic trend: from SiTe to PbTe, the differences of the calculated quasiparticle band gap, optical gap, and further exciton binding energy along different directions tended to decrease. We demonstrated that these anisotropic electronic and optical properties originate from the structural anisotropy, which in turn is the result of Coulomb repulsion between non-bonding electron pairs. Our theoretical results provide a deeper understanding of the anisotropic properties of group-IV telluride monolayers.

show abstract

“…To conclude, let us show that the relation (37) between the MCNs and the axion angle remains valid for gapless spectra. Equations ( 42) and (43) give μ G + μ X = W A , while θ is equal to the sum of Berry phases of vanishingly small loops around the nodes at A [13].…”

Section: B Gapless Wannier Band Structurementioning

confidence: 88%

“…DFT calculations reveal that the system with an optimized lattice constant of a = 6.16 Å is situated 0.4 eV above the convex hull and is dynamically unstable [36], and that a buckled structure that breaks mirror symmetry is energetically favored [37]. These results imply that a flat SnTe monolayer 195103-10 is not likely to be experimentally relevant.…”

Section: A Unbuckled Monolayer Of Sntementioning

confidence: 98%

Mirror Chern numbers in the hybrid Wannier representation

et al. 2021

View full text Add to dashboard Cite

The topology of electronic states in band insulators with mirror symmetry can be classified in two different ways. One is in terms of the mirror Chern number, an integer that counts the number of protected Dirac cones in the Brillouin zone of high-symmetry surfaces. The other is via a Z 2 index that distinguishes between systems that have a nonzero quantized orbital magnetoelectric coupling ("axion-odd"), and those that do not ("axioneven"); this classification can also be induced by other symmetries in the magnetic point group, including time reversal and inversion. A systematic characterization of the axion Z 2 topology has previously been obtained by representing the valence states in terms of hybrid Wannier functions localized along one chosen crystallographic direction, and inspecting the associated Wannier band structure. Here we focus on mirror symmetry, and extend that characterization to the mirror Chern number. We choose the direction orthogonal to the mirror plane as the Wannierization direction and show that the mirror Chern number can be determined from the winding numbers of the touching points between Wannier bands on mirror-invariant planes and from the Chern numbers of flat bands pinned to those planes. In this representation, the relation between the mirror Chern number and the axion Z 2 index is readily established. The formalism is illustrated by means of ab initio calculations for SnTe in the monolayer and bulk forms, complemented by tight-binding calculations for a toy model.

show abstract

Electronic states of SnTe and PbTe (001) monolayers with supports

Cited by 12 publications

References 36 publications

Strain-induced gauge and Rashba fields in ferroelectric Rashba lead chalcogenide PbX monolayers ( X=S , Se, Te)

Strain-induced gauge and Rashba fields in ferroelectric Rashba lead chalcogenide PbX monolayers ( X=S , Se, Te)

Anisotropic to Isotropic Transition in Monolayer Group-IV Tellurides

Mirror Chern numbers in the hybrid Wannier representation

Contact Info

Product

Resources

About