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DOE OSTI · 1977049

Q-POP-Thermo: A general-purpose thermodynamics solver for ferroelectric materials

Zorn, Jacob A.·Wang, Bo·Chen, Long-Qing
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Abstract

We report that Q-POP-Thermo is a program designed to compute thermodynamic monodomain equilibrium states and their properties for ferroelectric single crystals and thin films based on the Landau-Ginzburg-Devonshire (LGD) Theory. Utilizing symbolic manipulation with the SymPy Library, the governing equations along with appropriate boundary conditions are solved for speedy minimization of the free energy of a crystal. Utilizing the popular Differential Evolution algorithm, with appropriate hybridization, multiple phase diagrams, such as the pressure-temperature phase diagram for bulk single crystals and the common strain-temperature phase diagram for monodomain thin-film systems can be readily generated. Furthermore, a variety of material properties of stable ferroelectric phases, including dielectric, piezoelectric, and electrocaloric properties, can simultaneously be calculated. Validation studies are presented for both thin-film and single crystal systems to test the effectiveness and capability of the open-source program.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS97 MATHEMATICS AND COMPUTINGLandau-Ginzburg-Devonshire modeldifferential evolutionferroelectricsthermodynamics

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Zorn, Jacob A., Wang, Bo, Chen, Long-Qing. 2022-06-01. Q-POP-Thermo: A general-purpose thermodynamics solver for ferroelectric materials. https://doi.org/10.1016/j.cpc.2022.108302

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