论文标题
旋转式的Weyl锥和巨大的异常Nernst效果
Spin-polarized Weyl cones and gigantic anomalous Nernst effect in ferromagnetic Heusler films
论文作者
论文摘要
Weyl半法定的特征是在动量空间中存在无质量带分散。当Weyl半准遇到磁性时，由于其拓扑性质而出现了大的异常运输特性。在这里，使用$ Initu $旋转和角度分辨的光电子光谱与$ ab \ initio $计算相结合，我们可视化旋转偏振的Weyl锥和铁电磁CO $ _2 $ mNGA薄膜的平面表面状态，并具有全面透射式磁化。我们证明，当磁化强度诱导的LIFSHITZ量子关键点的巨大的Weyl锥接近Fermi Energy时，异常的大厅和NERNST电导率会系统地生长，直到$ \ sim 6.2 $ \ $ \ $ \rmμvk^k^{-1} $均在室内温度下。鉴于这种拓扑量子状态和全面浪漫磁化，CO $ _2 $ MNGA膜有望实现高效率热通量和磁场传感设备，可在室温和零视野下操作。
Weyl semimetals are characterized by the presence of massless band dispersion in momentum space. When a Weyl semimetal meets magnetism, large anomalous transport properties emerge as a consequence of its topological nature. Here, using $in-situ$ spin- and angle-resolved photoelectron spectroscopy combined with $ab\ initio$ calculations, we visualize the spin-polarized Weyl cone and flat-band surface states of ferromagnetic Co$_2$MnGa films with full remanent magnetization. We demonstrate that the anomalous Hall and Nernst conductivities systematically grow when the magnetization-induced massive Weyl cone at a Lifshitz quantum critical point approaches the Fermi energy, until a high anomalous Nernst thermopower of $\sim 6.2$ $\rm μV K^{-1}$ is realized at room temperature. Given this topological quantum state and full remanent magnetization, Co$_2$MnGa films are promising for realizing high efficiency heat flux and magnetic field sensing devices operable at room temperature and zero-field.
