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arXiv · 1404.5459

Elastocaloric response of PbTiO3 predicted from a first-principles effective Hamiltonian

Jordan A. Barr·Scott P. Beckman·Takeshi Nishimatsu
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Abstract

A first-principles based effective Hamiltonian is used within a molecular dynamics simulation to study the elastocaloric effect in PbTiO3. It is found that the transition temperature is a linear function of uniaxial tensile stress. Negative temperature change is calculated, when the uniaxial tensile stress is switched off, as a function of initial temperature Delta-T(T_initial). It is predicted that the formation of domain structures under uniaxial tensile stress degrades the effectiveness of the elastocaloric effect.

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Jordan A. Barr, Scott P. Beckman, Takeshi Nishimatsu. 2014-04-22. Elastocaloric response of PbTiO3 predicted from a first-principles effective Hamiltonian. https://doi.org/10.7566/jpsj.84.024716

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