Anisotropic magnetoresistance (AMR) ratio and anomalous Hall conductivity (AHC) in PdPt/Y 3 Fe 5 O 12 (YIG) system are tuned significantly by spin orbital coupling strength ξ through varying the Pt concentration. For both Pt/YIG and Pd/YIG, the maximal AMR ratio is located at temperatures for the maximal susceptibility of paramagnetic Pt and Pd metals. The AHC and ordinary Hall effect both change the sign with temperature for Pt-rich system and vice versa for Pd-rich system. The present results ambiguously evidence the spin polarization of Pt and Pd atoms in contact with YIG layers. The global curvature near the Fermi surface is suggested to change with the Pt concentration and temperature. PACS numbers: 72.25.Mk, 72.25.Ba, 75.70.-i * Correspondence author. Electronic mail: shiming@tongji.edu.cn 1 Generation, manipulation, and detection of pure spin current are popular topic in the community of spintronics because of its prominent advantage of negligible Joule heat in spintronic devices [1][2][3][4][5] . Pure spin current can be generated by spin Hall effect, spin Seebeck effect (SSE), and etc. By spin Hall effect, the pure spin current can be achieved in semiconductors due to strong spin orbital coupling (SOC). In the SSE approach, the spin current is produced in ferromagnetic materials with a temperature gradient and injected into another nonmagnetic layer through the interface. In general, the pure spin current cannot be probed by conventional electric approach. Instead, it is detected by inverse spin Hall effect 6,7 .With strong SOC in Pt layers and long spin diffusion length in Y 3 Fe 5 O 12 (YIG) insulator layers, the Pt/YIG systems are particularly suitable for design and fabrication of spintronic devices [8][9][10][11][12][13][14][15][16][17] . In studies of the SSE phenomena of Pt/YIG system, the SEE and the anomalous Nernst effect were argued to be entangled 9 , where the latter comes from the spin polarization due to the magnetic proximity effect (MPE) of the nearly ferromagnetic Pt layers. Many attempts have been made to study the MPE in Pt/YIG system. Since the atomic magnetic moment of Pt is too small to be measured by magnetometry, anisotropic magnetoresistance (AMR) and anomalous Hall effect (AHE) have been investigated intensively as a function of the Pt layer thickness and sampling temperature (T ) [10][11][12][13][14][15][16] . Up to date, however, magnetotransport results are controversial. The AMR ratio of Pt/YIG system exhibits an angular dependence different from the conventional AMR in magnetic films, and it changes nonmonotonically with the Pt layer thickness. Although these phenomena were attributed to spin Hall magnetoresistance (SMR) 14,15 instead of the conventional AMR, the nonmonotonic variation of the AMR with T cannot be understood in the SMR model 13 . Moreover, the ferromagnetic ordering in Pt layers was proved by the anomalous Hall effect (AHE) in Pt/YIG system 9 . In particular, the mechanism of the observed sign change of the AHE with T is still unclear. Very rece...

Computing vibrational properties of crystals in the presence of complex defects often necessitates the use of (semi-)empirical potentials, which are typically not well characterized for perfect crystals. Here we explore the efficacy of a commonly used embedded-atomempirical interatomic potential for the U x Th1−x O2 system, to compute phonon dispersion, lifetime, and branch specific thermal conductivity. Our approach for ThO2 involves using lattice dynamics and the linearized Boltzmann transport equation to calculate phonon transport properties based on second and third order force constants derived from the empirical potential and from first-principles calculations. For UO2, to circumvent the accuracy issues associated with first-principles treatments of strong electronic correlations, we compare results derived from the empirical interatomic potential to previous experimental results. It is found that the empirical potential can reasonably capture the dispersion of acoustic branches, but exhibits significant discrepancies for the optical branches, leading to overestimation of phonon lifetime and thermal conductivity. The branch specific conductivity also differs significantly with either first-principles based results (ThO2) or experimental measurements (UO2). These findings suggest that the empirical potential needs to be further optimized for robust prediction of thermal conductivity both in perfect crystals and in the presence of complex defects.

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