Validating First-Principles Phonon Lifetimes via Inelastic Neutron Scattering
Enda Xiao, Hao Ma, Matthew S. Bryan, Lyuwen Fu, J. Matthew Mann, Barry Winn, Douglas L. Abernathy, Raphaël P. Hermann, Amey R. Khanolkar, Cody A. Dennett, David… 展开作者
Enda Xiao, Hao Ma, Matthew S. Bryan, Lyuwen Fu, J. Matthew Mann, Barry Winn, Douglas L. Abernathy, Raphaël P. Hermann, Amey R. Khanolkar, Cody A. Dennett, David H. Hurley, Michael E. Manley, Chris A. Marianetti
Phonon lifetimes are a key component of quasiparticle theories of transport, yet first-principles lifetimes are rarely directly compared to inelastic neutron scattering (INS) results. Existing comparisons show discrepancies even at temperatures where perturbation theory is expected to be reliable. In this work, we demonstrate that the reciprocal space voxel ($q$-voxel), which is the finite region in reciprocal space required in INS data analysis, must be explicitly accounted for within theory in order to draw a meaningful comparison. We demonstrate accurate predictions of peak widths of the scattering function when accounting for the $q$-voxel in CaF$_2$ and ThO$_2$. Passing this test implies high fidelity of the phonon interactions and the approximations used to compute the Green's function, serving as critical benchmark of theory, and indicating that other material properties should be accurately predicted; which we demonstrate for thermal conductivity.
First-principles calculations of phonon frequencies, lifetimes and spectral functions from weak to strong anharmonicity: the example of palladium hydrides
Electric field dependent structural and vibrational properties of the Si(100)-H(2 \times 1) surface and its implications for STM induced hydrogen desorption
Observation of coherently modulated thermal phonon band and lifetime in superlattice
The University of Tokyo（东京大学）；Japan Synchrotron Radiation Research Institute (JASRI)（日本同步辐射研究机构）；Institute of Industrial Science, University of Tokyo（东京大学工业科学研究所）；Materials Dynamics Laboratory, RIKEN SPring-8 Center（理化学研究所SPring-8中心材料动力学实验室）；Institute of Engineering Innovation, The University of Tokyo（东京大学工程创新研究所）；Institute for Nano Quantum Information Electronics, The University of Tokyo（东京大学纳米量子信息电子学研究所）
Description of resonant inelastic x-ray scattering in correlated metals
为了充分利用共振非弹性X射线散射（RIXS）的潜力和多功能性，必须开发通过计算解释不同RIXS贡献的能力，包括相关材料的第一原理对动量转移的依赖性。为了实现这一目标，我们提出了一种新的方法来计算完整的RIXS响应的相关金属在一个公正的方式。通过比较的测量和计算，调整的入射光子能量的Fe L $_3$吸收共振的示例性材料BaFe $_2$作为$_2$的宽的一部分，我们表明，RIXS响应BaFe $_2$作为$_2$占主导地位的直接通道的贡献，包括拉曼响应低于阈值，我们解释为有限的芯孔寿命加宽的结果。计算最初是在第一性原理Bethe-Salpeter框架内进行的，然后我们通过与中间态激发的有效谱函数进行卷积来显着改进该框架。我们构造这个光谱函数，也从第一性原理，通过采用累积展开的格林函数和执行实时依赖于时间的密度泛函理论计算的电子系统的响应的扰动的中间态激发。重要的是，这使我们能够从第一原理评估间接RIXS响应，解释晶体结构的完整周期性并依赖于动量转移。
