籠目結構 FeGe 因為其角共享三角形結構而展現出多種特性。在較早的研究中表明了 FeGe 為一種反鐵磁性樣品，其在低溫處表現出電荷密度波以及自旋傾斜，且量測到了異常霍爾效應，並且研究表示電荷密度波與異常霍爾效應的產生相關，而另一研究指出了對樣品進行退火可以對電荷密度波的存在與否產生影響。對此，本研究透過對不同退火溫度的樣品進行霍爾電阻率、磁阻以及磁性實驗來分析電荷密度波與異常霍爾效應之間的關係。經過退火的樣品分別為：以 320°C 退火、具有長程電荷密度波的樣品，以及以 560°C 退火、不具有電荷密度波的樣品，且中子散射測量顯示，這兩個樣品在不同的溫度下皆會出現自旋傾斜現象。實驗中發現兩個樣品皆存在異常霍爾效應，此結果顯示了異常霍爾效應並非源自於電荷密度波，而是來自於自旋傾斜，亦即拓撲霍爾效應所致。

A kagome lattice FeGe exhibits a variety of physical properties due to its corner-sharing triangular structure. Previous study has shown that FeGe is an antiferro-magnetic material that exhibits charge density wave (CDW) order and spin canting at low temperatures, along with a measurable anomalous Hall effect (AHE). The study has suggested that CDW order is associated with the emergence of the AHE. Another study reported that thermal annealing can influence the presence or absence of the CDW order. In this work, we investigate the relationship between CDW and AHE by performing Hall resistivity, magnetoresistance, and magnetization measurements on FeGe samples annealed at different temperatures. The samples include a 320°C annealed sample with long-range CDW order, and a 560°C annealed sample without CDW. In both samples, the spin canting occurred below different temperatures are observed in neutron scattering measurements. Notably, the AHE is observed in both cases. These results indicate that the AHE does not originate from CDW order, but rather from spin canting, i.e., the topological Hall effect (THE).

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