Thermal Transport in Crystalline and Non-crystalline Solids: Theory and Experiments: Fundamentals of Phonon Mediated Thermal Transport
Sponsored by: TMS Structural Materials Division, TMS: Nuclear Materials Committee
Program Organizers: Marat Khafizov, Ohio State University; Michael Manley, Oak Ridge National Laboratory; Krzysztof Gofryk, Idaho National Laboratory; Aleksandr Chernatynskiy, Missouri Science and Technology University
Monday 8:00 AM
February 24, 2020
Room: 18
Location: San Diego Convention Ctr
Session Chair: Marat Khafizov, Ohio State University; Michael Manley, Oak Ridge National Laboratory
8:00 AM Invited
Phonon Dispersion and Linewidth in ThO2 Measured by Neutron Scattering: Matthew Bryan1; Lyuwen Fu2; Matthew Mann3; Chris Marianetti2; Michael Manley1; 1Oak Ridge National Laboratory; 2Columbia University; 3Air Force Research Laboratory
Recent inelastic neutron scattering measurements of single crystal ThO2, including the linewidth and dispersion are reported as a function of temperature. Comparisons with simulation results and the iso-structural UO2 dispersion and linewidths are made. Special interest will be given to the resulting thermal conductivity as a function of temperature.
8:30 AM Invited
Thermal Transport in ThO2: Chris Marianetti1; 1Columbia University
State-of-the-art first-principles techniques have been used to calculate the space group irreducible cubic and quartic phonon interactions in ThO2. Phonon linewidths are predicted using perturbation theory in addition to classical mechanics; and the results are compared to recent experimental measurements. Additionally, the phonon interactions are used to predict thermal conductivity both via the Boltzmann Equation and linear response in the classical limit; and these results are compared to experiment. Finally, attention is given to oxygen sublattice melting and its affect on thermal conductivity and other relevant observables.
9:00 AM
Study of Thermal Transport Properties of Thorium Dioxide Single Crystals: Narayan Poudel1; Xiaxin Ding1; Matthew Mann2; Krzysztof Gofryk1; 1Idaho National Laboratory; 2Air Force Research Laboratory
Thorium dioxide (ThO2) crystalizes into the CaF2-type cubic structure, similar to other members of the AnO2 (An = Th-Am) family. It forms stoichiometrically and is a wide-gap transparent insulator (Eg~5-6 eV). The thermodynamic and thermal transport properties of ThO2 single crystals have not been studied extensively, especially at low temperatures despite its importance in nuclear fuel technology. Here, we present our detailed measurements of the thermal conductivity, heat capacity, and magnetization of ThO2 single crystals, obtained from room temperature down to 2 K. In this temperature range, many different scattering mechanisms such as boundary, defects, and/or phonon-phonon dominate the heat transport in this material. For these studies, large and good quality single crystals of ThO2 have been synthesized by hydrothermal method. The observed results on ThO2 will be compared with UO2, especially in the context of impact of 5f-electrons on thermodynamic and transport behavior in these materials.
9:20 AM Cancelled
Lattice Dynamics and Thermodynamics of Strongly Anharmonic Solids via Bayesian Learning: Taishan Zhu1; Jeffrey Grossman1; 1Massachusetts Institute of Technology
Strongly anharmonic solids have been widely sought, ranging from thermoelectrics to multiferroics and to shape-memory materials, but the effects of strong anharmonicity to their thermodynamic and transport properties are less understood. In this work, we extend our earlier crystal graph convolutional neural network framework, and explore an alternative Bayesian description for the vibrational modes and their transport in strongly anharmonic solids exhibiting soft modes. We demonstrate our theory on a one-dimensional toy lattice, including a probabilistic extension to the conventional phononic dispersion relationship, as well as its consequences to lattice conductivity, other thermal properties, and phase transition. This Bayesian framework also provides naturally an uncertainty quantifying scheme for these physical quantities. Our theory is then extended to two halide perovskites: all inorganic CsPbI3 and hybrid inorganic-organic MAPbI3, and our Bayesian predictions are compared with existing experiments of heat capacity and lattice conductivity.
9:40 AM Break
10:00 AM Invited
Multi Scale Modeling of the Thermal Conductivity: Combining First Principle Calculations with Monte Carlo: Laurent Chaput1; David Lacroix1; 1University De Lorraine
Since the last few years it has been possible to determine the lattice thermal conductivity of semiconductors and insulators from first principle calculations. However, those computations are intrinsically limited to bulk crystals.In this talk we present a method combining ab initio calculations and the Monte Carlo method to obtain the thermal conductivity of nanostructures. The idea is to parametrize the Boltzmann equation with material properties computed for the bulk materials using ab initio calculation, and then to solve the Boltzmann equation in real space using the Monte Carlo method to take into account the boundary conditions. Several examples, based on different materials and nanostructures, will be considered.
10:30 AM Invited
Advancing Insights into Phonon Thermal Transport with Theory/experiment Interactions: Lucas Lindsay1; 1Oak Ridge National Laboratory
Computational materials physics is now playing an increasingly important role in developing fundamental insights into the lattice thermal conductivity of solids, a fundamentally important parameter that determines the utility of a material for energy-related applications including thermoelectricity, nuclear power generation, heat dissipation and manipulation, and thermal analogs to electronic components. Here I will discuss how predictive first principles Peierls-Boltzmann transport calculations can guide our understanding of lattice behaviors and thermal transport via comparison with measured observables. In particular, I will highlight work related to ultrahigh and ultralow thermal conductivity extremes, and the relationships of mode-dependent phonon properties (e.g., lifetimes, mean free paths, etc.) in determining transport – all in the context of theory/experiment interactions. L.L. acknowledges support from the U. S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.
11:00 AM Invited
Lattice Thermal Conductivity of Quartz at High Pressure and Temperature from the Boltzmann Transport Equation: Xue Xiong1; Eugene Ragasa2; Aleksandr Chernatynskiy3; DaWei Tang4; Simon Phillpot2; 1Chinese Academy of Sciences; 2University of Florida; 3Missouri University of Science and Technology; 4Dalian University of Technology
Knowledge of thermal conductivities of materials in the Earth’s crust, and mantle and their dependence on temperature and pressure, is required for quantitative calculations in geology and geophysics problems. As it is more than 60 mass% of the crust and ~45 mass% of the mantle, silica is a prototype material in which to consider the combined effects of temperature and pressure. The thermal conductivities along the basal and hexagonal directions of α-quartz silica, the low-temperature form of crystalline SiO2, are predicted from the solution of the Boltzmann transport equation combined with a standard empirical potential, with temperature up to 900 K and pressure as high as 4 GPa. The thermal conductivity, influenced by temperature and pressure, is analyzed based on phonon properties, including spectral thermal conductivity, dispersion relation, density of states, lifetime and probability density distribution function.