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Anisotropic carrier mobility in two-dimensional materials with tilted Dirac cones: theory and application
Ting Cheng1, Haifeng Lang, Zhenzhu Li
1College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China. LiuZhiRong@pku.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|August 16, 2017
Summary
We theoretically investigated carrier mobility in semimetals with tilted Dirac cones. Tilting significantly reduces mobility, but 8B-Pmmn borophene shows higher mobility than graphene.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Theoretical Physics
Background:
- Semimetals with tilted Dirac cones are promising for electronic applications.
- Understanding intrinsic carrier mobility is crucial for device performance.
Purpose of the Study:
- To theoretically investigate the intrinsic carrier mobility in semimetals with tilted Dirac cones.
- To derive an analytical formula for carrier mobility considering acoustic phonon scattering.
- To apply the derived theory to 8B-Pmmn borophene and borophane.
Main Methods:
- Theoretical investigation of carrier mobility under acoustic phonon scattering.
- Derivation of an analytical formula for carrier mobility.
- Application of the formula to specific 2D materials (borophene and borophane).
Main Results:
- An analytical formula for carrier mobility was obtained.
- Tilting of Dirac cones was found to significantly reduce carrier mobility.
- 8B-Pmmn borophene exhibits high carrier mobilities (14.8-28.4 × 10^5 cm^2 V^-1 s^-1), exceeding that of graphene.
- Borophane shows lower carrier mobility than 8B-Pmmn due to a smaller elastic constant.
Conclusions:
- The study provides a theoretical framework for understanding carrier mobility in tilted Dirac cone semimetals.
- 8B-Pmmn borophene demonstrates superior intrinsic carrier mobility compared to graphene.
- Material properties like elastic constants play a critical role in determining carrier mobility in these systems.
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