Influence of point defects on the phonon thermal conductivity and phonon density of states of Bi2Te3
Bedoya-Martinez ON, Hashibon A, Elsaesser C (2016)
Publication Type: Journal article
Publication year: 2016
Journal
Book Volume: 213
Pages Range: 684-693
Journal Issue: 3
Abstract
The influence of point defects on the lattice thermal conductivity and vibrational properties of Bi2Te3 were studied by using equilibrium and non-equilibrium molecular-dynamics simulations. Three types of point defects at various concentrations were considered, namely Bi and Te vacancies and Bi anti-sites. It is shown that point defects can result in a reduction of up to 80% of the bulk thermal conductivity. A detailed analysis of the phonon density of states (PDOS) of the studied systems is provided. Element (Bi or Te) and orientation (in-plane or cross-plane) resolved PDOS were calculated. In agreement with experimental observations and other simulations, features in the PDOS were identified with specific atomic and orientation contributions. Systems containing point defects exhibit a broadening of the PDOS peaks as the defect concentration increases, which is due to the disorder induced by the defects. Such disorder leads to a higher phonon scattering and thus to a lower lattice thermal conductivity. Tuning the point defect type and concentrations during growth may, therefore, provide a route for optimizing Bi2Te3 based thermoelectric devices.
Involved external institutions
Germany (DE)How to cite
APA:
Bedoya-Martinez, O.N., Hashibon, A., & Elsaesser, C. (2016). Influence of point defects on the phonon thermal conductivity and phonon density of states of Bi2Te3. physica status solidi (a), 213(3), 684-693. https://dx.doi.org/10.1002/pssa.201532436
MLA:
Bedoya-Martinez, O. N., A. Hashibon, and C. Elsaesser. "Influence of point defects on the phonon thermal conductivity and phonon density of states of Bi2Te3." physica status solidi (a) 213.3 (2016): 684-693.
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