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DOE OSTI · 1899784

Relaxation time approximations in PAOFLOW 2.0

Jayaraj, Anooja·Siloi, Ilaria·Fornari, Marco·Nardelli, Marco Buongiorno
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Abstract

Abstract Regardless of its success, the constant relaxation time approximation has limited validity. Temperature and energy dependent effects are important to match experimental trends even in simple situations. We present the implementation of relaxation time approximation models in the calculation of Boltzmann transport in 2.0 and apply those to model band-structures. In addition, using a self-consistent fitting of the model parameters to experimental conductivity data, we provide a flexible tool to extract scattering rates with high accuracy. We illustrate the approximations using simple models and then apply the method to GaAs, Si, $$\hbox {Mg}_3\hbox {Sb}_2$$ Mg 3 Sb 2 , and $$\hbox {CoSb}_3$$ CoSb 3 .

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72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDScondensed matter physicselectronic structuretheory and computationthermoelectrics

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Jayaraj, Anooja, Siloi, Ilaria, Fornari, Marco, Nardelli, Marco Buongiorno. 2022-03-23. Relaxation time approximations in PAOFLOW 2.0. https://doi.org/10.1038/s41598-022-08931-5

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