拓樸絕緣體其特殊的能帶結構導致其內部絕緣而在邊緣或表面導電。MnSb2Te4已經被預測為一種本質性磁性拓樸絕緣體，當磁性元素Mn摻雜進Sb2Te3三維拓撲絕緣體時，會破壞時間反衍對稱性(time reversal symmetry)，導致量子異常霍爾效應(Quantum Anomalous Hall Effect, QAHE)出現。
利用分子束磊晶系統(Molecular Seam Epitaxy, MBE)成長MnSb2Te4單晶薄膜，利用X光繞射儀(X-ray diffractometer, XRD)、原子力顯微鏡(Atomic force microscope, AFM)、X射線光電子能譜(X-ray photoelectron spectroscopy, XPS)、高解析穿透式電子顯微鏡(High Resolution Transmission electron microscope, HR-TEM)、EDS能量散佈儀(Energy Dispersive Spectrometer, EDS)、拉曼光譜儀(Raman)等各式儀器確認晶體結構、摻雜濃度、表面狀態、薄膜內部原子分布狀態等。上述實驗完成後，取結果最優之高品質樣品薄膜，進行顯影以及蝕刻製成，以超導量子干涉震動儀(Superconducting Quantum Interference Device Vibrating Sample magnetometer, SQUID VSM)以及物理性質量測系統(Physical Properties Measurement Systems, PPMS)觀察樣品的磁電性質。
利用SQUID量測，得知MnSb2Te4薄膜內部磁性具有反鐵磁與鐵性兩種貢獻，磁性貢獻來源會隨著Mn摻雜濃度上升而變更，摻雜濃度越高，鐵磁性貢獻就會越明顯，而薄膜的尼爾溫度TN(Neel’ temperature)的溫度範圍大約落在12K~22K。透過PPMS量測可以更進一步確認TN(Neel’ temperature)的溫度會落在於20K左右；遺憾的是Rxx量測並未觀察到異常霍爾效應(Anomalous Hall effect)的出現，其原由還有待更進一步的確認；Rxy量測中確認了MnSb2Te4單晶薄膜的傳輸性質為p-type形式。

The unique band structure of topological insulators results in an insulating interior while being conductive at the edges or surface. MnSb2Te4 has been predicted to be an intrinsic magnetic topological insulator. When the magnetic element Mn is doping into the three-dimensional topological insulator Sb2Te3, it breaks time reversal symmetry, leading to the emergence of the Quantum Anomalous Hall Effect (QAHE).

In this study, We grown the MnSb2Te4 single-crystal thin film by the Molecular Beam Epitaxy (MBE) system, and using some of different types of instruments such as X-ray diffractometer (XRD), Atomic Force Microscope (AFM), X-ray photoelectron spectroscopy (XPS), High Resolution Transmission Electron Microscope (HR-TEM), and Energy Dispersive Spectrometer (EDS) to verify the crystal structure, doping concentration, surface condition, and internal atomic distribution of the thin films. Then using the Superconducting Quantum Interference Device Vibrating Sample magnetometer (SQUID VSM) and Physical Properties Measurement Systems (PPMS) to measure the magnetic and electrical properties of the samples.

By using SQUID, we found that the magnetic properties within MnSb2Te4 thin film exhibit contributions from both antiferromagnetic and ferromagnetic components, when doping of Mn increases, the ferromagnetic contribution becomes more pronounced, and its Neel’ temperature is about 12~22K. Through PPMS measurements can be further confirmed that the Neel temperature is about 20K. Unfortunately, the Rxx experiment did not observe the Anomalous Hall effect (AHE), and the reason still requires further confirmation. The Rxy experiment exhibit MnSb2Te4 thin films is p-type transport behavior.

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