Experimental study of topological phases in strongly correlated system

我们系统地研究了FexGa4-x系统中反常能斯特效应(ANE)的成分依赖关系。我们的研究为人工智能的应用提供了一个理想的候选者。首先，我们在Fe3.09Ga0.91中发现了5.4μV/K的峰值，这是迄今为止在多晶磁性化合物中观察到的最大的室温值。此外，我们发现这种在多晶Fe3Ga中的大的室温ANE对Fe的掺杂具有很强的抵抗力，这使得这种材料成为一个很有前途的候选材料。其次，我们的工作提供了通过Berry曲率工程来调谐反常能斯特效应的实验实现。我们的理论分析表明，Fe掺杂增加了交换分裂效应，从而使Berry曲率调谐到费米能级附近。

We systematically studied the composition dependence of anomalous Nernst effect (ANE) in FexGa4-x system. Our research provides an ideal candidate for application using ANE. Firstly, We find a peak value of 5.4 μV/K in Fe3.09Ga0.91 which is the largest room-temperature value so far observed in polycrystalline magnetic compounds. Moreover, we found this large room-temperature ANE in the polycrystalline Fe3Ga is robust against Fe doping, making this material a promising candidate. Secondly, our work provides an experimental realization of the tuning of the anomalous Nernst effect by the Berry curvature engineering. Our theoretical analysis suggests that the Fe doping increases the exchange splitting effect, thereby tuning Berry curvature near the Fermi energy.