Zhou Shuxiang, Xiao Enda, Ma Hao, Gofryk Krzysztof, Jiang Chao, Manley Michael E, Hurley David H, Marianetti Chris A
Idaho National Laboratory, Idaho Falls, Idaho 83415, USA.
Department of Chemistry, Columbia University, New York, New York 10027, USA.
Phys Rev Lett. 2024 Mar 8;132(10):106502. doi: 10.1103/PhysRevLett.132.106502.
Computing thermal transport from first-principles in UO_{2} is complicated due to the challenges associated with Mott physics. Here, we use irreducible derivative approaches to compute the cubic and quartic phonon interactions in UO_{2} from first principles, and we perform enhanced thermal transport computations by evaluating the phonon Green's function via self-consistent diagrammatic perturbation theory. Our predicted phonon lifetimes at T=600 K agree well with our inelastic neutron scattering measurements across the entire Brillouin zone, and our thermal conductivity predictions agree well with previous measurements. Both the changes due to thermal expansion and self-consistent contributions are nontrivial at high temperatures, though the effects tend to cancel, and interband transitions yield a substantial contribution.
由于与莫特物理相关的挑战，从第一性原理计算UO₂中的热输运很复杂。在此，我们使用不可约导数方法从第一性原理计算UO₂中的三次和四次声子相互作用，并通过自洽图解微扰理论评估声子格林函数来进行增强的热输运计算。我们预测的T = 600 K时的声子寿命与我们在整个布里渊区的非弹性中子散射测量结果吻合良好，并且我们的热导率预测与先前的测量结果吻合良好。尽管高温下热膨胀和自洽贡献引起的变化往往相互抵消，但两者的影响都很显著，并且带间跃迁产生了很大的贡献。
