Two-dimensional Bi2Se3 monolayer with high mobility and enhanced optical absorption in the UV–visible light region

“…We obtained that the lattice constant of MoSe 2 is a = b = 3.32 Å and that of Bi 2 Se 3 is a = b = 4.18 Å, which is very close to the previous calculation value. [ 55,58 ] Due to the lattice mismatch of their primitive cells up to 23%, to ensure the accuracy of the calculation results, we build the

\sqrt{7}

\sqrt{7}

× R 19.1° MoSe 2 supercell and 2 × 2 × 1 Bi 2 Se 3 supercell. The lattice mismatch is reduced to 4.89%, which is acceptable in calculations.…”

Section: Resultsmentioning

confidence: 99%

“…First‐principles calculations of monolayer Bi 2 Se 3 also show that it has a high carrier mobility comparable to graphene's. [ 55 ] Tang et al reported millimeter and terahertz detectors based on a metal–TI–metal heterojunction, with the highest detectivity of 3.17 × 10 11 cm Hz −1/2 W −1 at room temperature. [ 56 ] Yang et al developed an epitaxial method to synthesize a Bi 2 Te 3 /WSe 2 vdWH.…”

Section: Introductionmentioning

confidence: 99%

First‐Principles Study of the Electronic and Optical Properties of Bi₂Se₃/MoSe₂ Heterojunction

Liu

et al. 2021

Physica Status Solidi (b)

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MoSe2 and Bi2Se3 are two kinds of 2D materials that are gradually receiving more attention because of their unique electronic and optical properties. Herein, a Bi2Se3/MoSe2 van der Waals heterojunction (vdWH) is constructed and the electronic and optical properties of the heterojunction are calculated using first‐principles calculations. The effects of the external electric field and the interlayer distance on the electronic properties of the heterojunction are also studied. The calculated results show that the inherent Bi2Se3/MoSe2 vdWH has a type‐2 band alignment with a very small indirect bandgap (28 meV). It also has strong spin–orbit coupling effects, and the characteristics of Zeeman splitting and Rashba splitting are observed at the same time. Both applying an external electric field and changing the interlayer distance can effectively modulate the band structure of the heterojunction; these modulation methods can change the band alignment of the vdWH from type‐2 to type‐3 or even type‐1, and the bandgap type can be changed from indirect to direct. The infrared absorption of the heterojunction is much higher than that of Bi2Se3 and MoSe2. All the calculation results show that the Bi2Se3/MoSe2 vdWH has good application prospects in optoelectronic and spintronic devices.

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“…The bismuth-based chalcogenide compounds, particularly, Bi 2 S 3 , Bi 2 Se 3 and Bi 2 Te 3 have gained special interest due to their unrivalled electronic, thermoelectric and optical properties, such as low thermal conductivity, large Seebeck coefficients, small effective carrier masses, and thickness-dependent bandgap. [1][2][3] Therefore, bismuth chalcogenide compounds are suitable for a wide variety of applications including thermoelectric energy conversion, 4 spintronics, 5 infrared photography, 6 photosensitive and optical devices. 7 Moreover, due to the feature of intralayer anisotropic crystal structures, the bismuth-based chalcogenide nanomaterials exhibit direction-dependent optical, thermal, electronic properties such as the transport of charge in different crystal axes, which can be profitable for invention of innovative devices like directionsensitive sensors and high-speed optoelectronic devices.…”

Section: Introductionmentioning

confidence: 99%

Prediction of two-dimensional bismuth-based chalcogenides Bi₂X₃(X = S, Se, Te) monolayers with orthorhombic structure: a first-principles study

Bafekry¹,

Fadlallah²,

Jappor³

et al. 2021

J. Phys. D: Appl. Phys.

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First-principles calculation is a very powerful tool for discovery and design of novel twodimensional materials with unique properties needed for the next generation technology. Motivated by the successful preparation of Bi2S3 nanosheets with orthorhombic structure in the last year [K. A. Messalea et al., Adv. Mater. Interfaces 7, 2001131 (2020)] herein we gain a deep theoretical insight into the crystal structure, stability, electronic and optical properties of Bi2X3 (X=S, Se, Te) monolayers of orthorhombic phase employing the first-principles calculations. The Molecular dynamics study, phonon spectra, criteria for elastic stability, and cohesive energy results confirm the desired stability of the Bi2X3 monolayers. From S, to Se and Te, the work function value as well as stability of the systems decrease due to the decline in electronegativity. Mechanical properties study reveals that Bi2X3 monolayers have brittle nature. The electronic bandgap values of Bi2S3, Bi2Se3 and Bi2Te3 monolayers are predicted by the HSE06 functional to be 2.05 eV, 1.20 eV and 1.16 eV, respectively. By assessing the optical properties, it has been found that Bi2X3 monolayers can absorb ultraviolet light. The high in-plane optical anisotropy offers an additional degree of freedom in the design of optical devices. The properties revealed in our survey will stimulate and inspire the search for new approaches of orthorhombic Bi2X3 (X=S, Se, Te) monolayers synthesis and properties manipulation for fabrication of novel nanoelectronic and optoelectronic devices.

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Two-dimensional Bi2Se3 monolayer with high mobility and enhanced optical absorption in the UV–visible light region

Cited by 22 publications

References 48 publications

Electronic and thermoelectric properties of semiconducting Bi₂SSe₂ and Bi₂S₂Se monolayers with high optical absorption

Electronic and thermoelectric properties of semiconducting Bi₂SSe₂ and Bi₂S₂Se monolayers with high optical absorption

First‐Principles Study of the Electronic and Optical Properties of Bi₂Se₃/MoSe₂ Heterojunction

Prediction of two-dimensional bismuth-based chalcogenides Bi₂X₃(X = S, Se, Te) monolayers with orthorhombic structure: a first-principles study

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Two-dimensional Bi2Se3 monolayer with high mobility and enhanced optical absorption in the UV–visible light region

Cited by 22 publications

References 48 publications

Electronic and thermoelectric properties of semiconducting Bi2SSe2 and Bi2S2Se monolayers with high optical absorption

Electronic and thermoelectric properties of semiconducting Bi2SSe2 and Bi2S2Se monolayers with high optical absorption

First‐Principles Study of the Electronic and Optical Properties of Bi2Se3/MoSe2 Heterojunction

Prediction of two-dimensional bismuth-based chalcogenides Bi2X3(X = S, Se, Te) monolayers with orthorhombic structure: a first-principles study

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Electronic and thermoelectric properties of semiconducting Bi₂SSe₂ and Bi₂S₂Se monolayers with high optical absorption

Electronic and thermoelectric properties of semiconducting Bi₂SSe₂ and Bi₂S₂Se monolayers with high optical absorption

First‐Principles Study of the Electronic and Optical Properties of Bi₂Se₃/MoSe₂ Heterojunction

Prediction of two-dimensional bismuth-based chalcogenides Bi₂X₃(X = S, Se, Te) monolayers with orthorhombic structure: a first-principles study