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Theoretical Calculation and Experimental Verification for Dislocation Reduction in Germanium Epitaxial Layers with Semicylindrical Voids on Silicon
Published on: July 17, 2020
Tunable bandgap in silicene and germanene
Zeyuan Ni1, Qihang Liu, Kechao Tang
1State Key Laboratory of Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871, PR China.
Nano Letters
|November 5, 2011
Summary
Applying an electric field opens a band gap in silicene and germanene, enabling their use as effective field-effect transistors at room temperature.
Area of Science:
- Condensed matter physics
- Materials science
- Nanotechnology
Background:
- Single-layer silicene and germanene are semimetallic materials with potential applications in electronics.
- Controlling the electronic properties of these 2D materials is crucial for device development.
Purpose of the Study:
- To investigate the effect of vertical electric fields on the electronic band structure of single-layer silicene and germanene.
- To explore the potential of these materials as field-effect transistors (FETs) operating at room temperature.
Main Methods:
- Ab initio calculations were employed to predict the electronic band structure modifications.
- Ab initio quantum transport simulations were performed on a dual-gated silicene FET model.
Main Results:
- A vertical electric field was predicted to open a band gap in both silicene and germanene.
- The band gap size increased linearly with increasing electric field strength.
- Quantum transport simulations confirmed the opening of a transport gap and demonstrated a significant switching effect in a silicene FET.
Conclusions:
- Biased single-layer silicene and germanene can effectively function as field-effect transistors at room temperature.
- The electric field-induced band gap opening is a viable mechanism for tuning the electronic properties of these materials for electronic applications.
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