Syariati Rifky, Wella Sasfan A, Suprayoga Edi, Muntini Melania S, Ishii Fumiyuki
Nanomaterials Research Institute, Kanazawa University, Kakuma-machi, Kanazawa, Ishikawa 920-1192, Japan.
Research Center for Quantum Physics, National Research and Innovation Agency (BRIN), South Tangerang 15214, Indonesia.
J Phys Condens Matter. 2024 Oct 14;37(2). doi: 10.1088/1361-648X/ad7d7d.
The anomalous Hall conductivity of all transition metal trihalides was explored using first-principles calculations. Employing the Fukui-Hatsugai-Suzuki method, we found that ferromagnetic monolayersBr(= Pd, Pt) possessed the quantized anomalous Hall conductivity (QAHC) with and without carrier doping. Due to unique QAHC, their transverse thermoelectric properties ofBr(= Pd, Pt) were investigated. Employing the semi-classical Boltzmann transport theory, the transverse thermoelectric coefficient of each monolayer was analyzed. Anomalous Nernst coefficients (ANCs) of theBrmonolayers were prominent both at and near the Fermi level. Under an assumed relaxation time of 10 fs, the maximum ANCs for the PdBr(PtBr) monolayer reached -54.1 (-23.3)V KatT=300 K upon doping with 1.21 × 10(5.64 × 10) holes cm. The large ANCs of theBrmonolayers were attributed to the opening of a narrow bandgap generated by spin-orbit coupling both at and near the Fermi level, which led to a large Seebeck-induced charge current and large anomalous Nernst conductivity. These results suggest that ferromagneticBrmonolayers have significant potential for application in thermoelectric devices.
利用第一性原理计算研究了所有过渡金属三卤化物的反常霍尔电导率。采用福井-初贝-铃木方法，我们发现铁磁单层溴化物（=钯、铂）在有和没有载流子掺杂的情况下都具有量子化反常霍尔电导率（QAHC）。由于独特的QAHC，研究了它们的横向热电性质。采用半经典玻尔兹曼输运理论，分析了每个单层的横向热电系数。溴单层的反常能斯特系数（ANC）在费米能级处及附近都很显著。在假设弛豫时间为10飞秒的情况下，钯溴（铂溴）单层在掺杂1.21×10（5.64×10）个空穴 cm时，在T = 300 K时的最大ANC达到-54.1（-23.3）V K。溴单层的大ANC归因于费米能级处及附近由自旋轨道耦合产生的窄带隙的打开，这导致了大的塞贝克感应电荷电流和大的反常能斯特电导率。这些结果表明，铁磁溴单层在热电装置中具有显著的应用潜力。
