Electron-phonon scattering and mean free paths in D-carbon
1School of Physical Science and Technology, Inner Mongolia University, Hohhot 010021, China. sdwang@imu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|February 6, 2020
Summary
Hot carrier scattering in D-carbon is dominated by phonons. Hot holes exhibit longer relaxation times and mean free paths than hot electrons due to distinct scattering intensities and band structures.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Physics
Background:
- Understanding hot carrier dynamics is crucial for advanced electronic and optoelectronic devices.
- D-carbon, a unique allotrope of carbon, presents novel electronic properties.
- Investigating carrier scattering mechanisms in D-carbon is essential for its technological applications.
Purpose of the Study:
- To investigate the hot carrier scattering rates in D-carbon.
- To identify the dominant phonon modes responsible for scattering.
- To compare the scattering behavior of electrons and holes in D-carbon.
Main Methods:
- First-principles simulations were employed to model D-carbon.
- The Wannier function interpolation method was utilized for accurate calculations.
- Mode-resolved scattering analysis was performed to understand phonon contributions.
Main Results:
- Optical and acoustic phonons primarily govern scattering near the valence and conduction band edges, respectively.
- Transverse optical phonons significantly influence scattering processes approximately 0.2 eV from band edges.
- Holes demonstrate considerably longer relaxation times than electrons near band edges.
Conclusions:
- Phonon scattering significantly impacts hot carrier behavior in D-carbon.
- D-carbon exhibits anisotropic carrier dynamics with holes having superior transport properties.
- These findings provide insights for designing D-carbon-based electronic devices.
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