Table 1 Energy difference between layers (EDiff) in types (ii) and (iii) and the hopping integral between layers (|t|) in types (i) and (iv)

From: Toward direct band gaps in typical 2D transition-metal dichalcogenides junctions via real and energy spaces tuning

EDiff (eV)

Type-(ii)

MoS2/WS2

MoSe2/WSe2

0.19

0.21

Type-(iii)

MoS2/MoSe2

WS2/WSe2

MoS2/WSe2

MoSe2/WS2

0.37

0.38

0.57

0.17

Energy of X/M atoms (eV)

S 3p

Se 4p

Mo 4d

W 5d

−7.01

−6.51

−3.75

−3.32

|t| (eV)

 

Unitcell

Supercella

Weaken ratio

MoS2 bilayer

0.50

0.39

78%

WS2 bilayer

0.42

0.33

78%

MoSe2 bilayer

0.51

0.40

77%

WSe2 bilayer

0.47

0.34

74%

  1. EDiff values between band edges of VB@Γ in the component layers of types (ii) and (iii) bilayers; and |t| values of VB@Γ in MX2 bilayers. For EDiff, the corresponding p- and d-orbital energy levels from pseudopotentials for X and M atoms of MX2 are also given as a reference. For |t|, the weaken ration is the |t| from supercell (with larger-angle twisting between layers) divided by that from the corresponding |t| of unitcell.
  2. aThe |t| of supercell is obtained from MX2 bilayer in the \((\sqrt{7}\times \sqrt{7}){{R}}38.2^{\circ}\) structure [refer to Fig. 1a(iv)].
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