Band structures and topological properties of twisted bilayer MoTe2 and WSe2

Abstract We calculate the electronic band structures and topological properties of twisted homobilayer transition metal dichalcogenides(t-TMDs), in particular, bilayer MoTe2 and WSe2 based on a low-energy effective continuum model. We systematically show how the twist angle, vertical electric field and pressure modify the band structures of t-TMDs, often accompanied by topological transitions.We find the variation of topological transitions mainly take place in a limited range of parameters. The electric field can efficiently tune the energy of the topmost second valence band to motify the Chern numbers of the topmost three valance bands. The topological property of the topmost first valance band can be modified by electric field and pressure, but doesn’t depend on twist angle. We show the band gap between the topmost second and third valance bands that both change from non-trivial to trivial closes at κ − -point of the moiré Brillouin zone.

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Electronic Band Structures and Magnetic Properties of Mn-Intercalated Compounds of 2H-Type Transition Metal Dichalcogenides

New Horizons in Low-Dimensional Electron Systems - Physics and Chemistry of Materials with Low-Dimensional Structures ◽

10.1007/978-94-011-3190-2_4 ◽

1992 ◽

pp. 55-69 ◽

Cited By ~ 1

Author(s):

Naoshi Suzuki ◽

Shigeki Tomishima ◽

Kazuko Motizuki

Keyword(s):

Magnetic Properties ◽

Transition Metal ◽

Transition Metal Dichalcogenides ◽

Band Structures ◽

Electronic Band ◽

Type Transition ◽

Intercalated Compounds ◽

Metal Dichalcogenides ◽

Electronic Band Structures

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Tuning band gaps of BN nanosheets and nanoribbons via interfacial dihalogen bonding and external electric field

Nanoscale ◽

10.1039/c4nr00008k ◽

2014 ◽

Vol 6 (15) ◽

pp. 8624-8634 ◽

Cited By ~ 50

Author(s):

Qing Tang ◽

Jie Bao ◽

Yafei Li ◽

Zhen Zhou ◽

Zhongfang Chen

Keyword(s):

Electric Field ◽

External Electric Field ◽

Band Gaps ◽

Band Structures ◽

Electronic Band ◽

Dft Computations ◽

Electronic Band Structures

DFT computations with dispersion corrections were performed to investigate dihalogen interactions and their effect on the electronic band structures of halogenated BN bilayers and aligned halogen-passivated zigzag BN nanoribbons (BNNRs).

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Shear-strain-mediated photoluminescence manipulation in two-dimensional transition metal dichalcogenides

2D Materials ◽

10.1088/2053-1583/ac351d ◽

2021 ◽

Author(s):

Hyeong-Yong Hwang ◽

Sehyuk Lee ◽

Yong-Hoon Kim ◽

Farman Ullah ◽

Chinh Tam Le ◽

...

Keyword(s):

Transition Metal ◽

Shear Strain ◽

Compressive Strain ◽

Transition Metal Dichalcogenides ◽

Normal Strain ◽

Two Dimensional ◽

Band Structures ◽

Electronic Band ◽

Selection Rules ◽

Metal Dichalcogenides

Abstract In two-dimensional transition metal dichalcogenides, normal strain can modulate electronic band structures, yet leaving the optical selection rules intact. In contrast, a shear strain can perturb the spin-valley locked band structures and possibly induce mixing of the spin subbands which in turn can transfer oscillator strength between spin-allowed bright and spin-forbidden dark excitons. Here, we report a novel scheme to manipulate photoluminescence in a monolayer WSe2-MoSe2 lateral heterostructures, controlled by an external bending method in which strong out-of plane shear strain (OSS) of up to 5.6% accompanies weak in-plane normal strain up to 0.72%. The spectra revealed a striking dependence on the bending direction that is stagnant in the negative (compressive) strain region and then rapidly changes with increasing positive (tensile) strain. The dependency of the photoluminescence signal under tensile bending was represented not only by the large energy shift (>40 meV) of the lowest excited states of both the WSe2 and MoSe2 monolayers, but also by the tendency to violate the optical selection rules that brightens (darkens) the excitons of the WSe2 (MoSe2) side. The analyses on the observed energy shifts and PL intensity changes confirm the different origins in compressive bending compared with tensile bending. The well-established band-anticrossing is identified to be affecting only the compressive deformation region. The spectral changes in the tensile region, on the other hand, originates mainly from the generation of an off-diagonal perturbation to a spin-specific Hamiltonian induced by OSS. The degree of spin-state mixing, which correlates precisely with the spin-flip coefficient of the theoretical model, is further represented by the OSS matrix elements, the spin splitting energy, and the shear deformation potential.

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Electronic band structures of NdFe3(BO3)4 and NdGa3(BO3)4 crystals: ab initio calculations

Ferroelectrics ◽

10.1080/00150193.2021.1888219 ◽

2021 ◽

Vol 575 (1) ◽

pp. 11-17

Author(s):

S. Krylova ◽

I. Gudim ◽

A. Aleksandrovsky ◽

A. Vtyurin ◽

A. Krylov

Keyword(s):

Ab Initio Calculations ◽

Ab Initio ◽

Band Structures ◽

Electronic Band ◽

Electronic Band Structures

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Synthesis, electrical behaviour, and crystal and electronic band structures of two different phases of the (SMeEt2)[Pd(dmit)2]2 salt. Consequences of cationic disorder on the electrical properties

Journal of Materials Chemistry ◽

10.1039/b102133h ◽

2001 ◽

Vol 11 (9) ◽

pp. 2205-2210 ◽

Cited By ~ 7

Author(s):

C. Faulmann ◽

M.-L. Doublet ◽

F. Granier ◽

B. Garreau de Bonneval ◽

I. Malfant ◽

...

Keyword(s):

Electrical Properties ◽

Electrical Behaviour ◽

Band Structures ◽

Electronic Band ◽

Electronic Band Structures ◽

Cationic Disorder

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Phase-selective active sites on ordered/disordered titanium dioxide enable exceptional photocatalytic ammonia synthesis

Chemical Science ◽

10.1039/d1sc03223b ◽

2021 ◽

Author(s):

Jinsun Lee ◽

Xinghui Liu ◽

Ashwani Kumar ◽

Yosep Hwang ◽

Eunji Lee ◽

...

Keyword(s):

Titanium Dioxide ◽

Active Sites ◽

Rational Design ◽

Ammonia Synthesis ◽

Reduction Reaction ◽

Band Structures ◽

Electronic Band ◽

Defect Sites ◽

Electronic Band Structures ◽

Reaction Routes

This work highlights the importance of a rational design for more energetically suitable nitrogen reduction reaction routes and mechanisms by regulating the electronic band structures with phase-selective defect sites.

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Electronic band structures of CuBa2Can−1CunO2n+2 and CuBa2Can−1CunO2n+1F (n=3–5)

Physica C Superconductivity ◽

10.1016/s0921-4534(01)00177-0 ◽

2001 ◽

Vol 357-360 ◽

pp. 108-111 ◽

Cited By ~ 42

Author(s):

N. Hamada ◽

H. Ihara

Keyword(s):

Band Structures ◽

Electronic Band ◽

Electronic Band Structures

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Molecular Vibrations in the Exciton Theory for Molecular Aggregates. II. Dimeric Systems

Australian Journal of Chemistry ◽

10.1071/ch9610344 ◽

1961 ◽

Vol 14 (3) ◽

pp. 344 ◽

Cited By ~ 2

Author(s):

EG McRae

Keyword(s):

Absorption Spectrum ◽

Perturbation Theory ◽

Fluorescence Spectra ◽

Numerical Calculations ◽

Molecular Vibrations ◽

Molecular Aggregates ◽

Absorption And Fluorescence Spectra ◽

Band Structures ◽

Electronic Band ◽

Electronic Band Structures

The theory of Part I of this series (McRae 1961) is developed in detail for dimeric systems. The simplest possible theory of the exciton states for a system of two non-rigid molecules is obtained through the use of perturbation theory. The theory makes possible the prediction of electronic band structures in absorption and fluorescence spectra as functions of the theoretical Davydov splitting for two rigid molecules. Numerical calculations are made for a dimer of a typical dye, and the results are compared with the observed absorption spectrum of the 1,1'-diethyl-2,2'-pyridocyanine iodide dimer.

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