本實驗是對混和價鍵系統CeMn2Si2-like (CeMn2.16Si1.84)做電性、磁性和熱性磁的研究， 我們可以在樣品CeMn2.16Si1.84上發現，當樣品放在外加高磁場(H=120 kOe)且低溫的環境下，會產生一個異常大的正磁阻，而樣品溫度在21K時，其磁阻產生高達548%的最大值，且當溫度低於21K時，磁阻值會隨著溫度的下降而變小。在磁性測量方面，當在外加低磁場(H < 100 Oe)下，樣品CeMn2.16Si1.84的溫度低於240K時，我們可以觀察到產生熱磁不可逆(thermomagnetic irreversibility,TMI)的現象，隨著外加磁場的增加，使的TMI效應慢慢變小且消失。在外加高磁場的環境下，因為樣品CeMn2.16Si1.84為混和價鍵系統，所以我們可以推測因為高磁場的存在，使的4f電子能階位移至費米能階附近，造成磁阻在低溫高磁場下有異常大的值存在，且樣品的TMI效應可能源自於鐵磁分量依附在反鐵磁有序結構或者自旋玻璃相。

The electrical, magnetic and thermal properties of the valence fluctuation system CeMn2Si2-like (CeMn2.16Si1.84) were studied. In a magnetic field of 12 T, as the temperature decreases the magnetoresistance of CeMn2.16Si1.84 becomes positive and reaches an unusually large value 548% at 21 K. Whereas, below 21 K, the magnetoresistance decreases as the temperature decreased. The anomalously high magnetoresistance might arise from the shifted f-band over the Fermi level by a magnetic field. In a low magnetic field (H < 100 Oe), large thermomagnetic irreversibility (TMI) was observed below ~ 240 K. The TMI behavior decreases with the increasing H, and disappears with the H large enough. This behavior can be explained by the antiferromagnetic component pinned in the overall ferromagnetic ordering structure, or spin-glass phases.

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