反鐵磁材料具備太赫茲共振、高儲存密度以及無雜散場的特性，讓該材料在記憶體的應用上極具潛力，但是反鐵磁靜磁矩為零的特性，使得反鐵磁的磁序和自旋不易被量測。二維反鐵磁材料NiPS3最近引起了極大的關注，這是因為NiPS3表現出強烈的磁性-激子偶合，進而導致超尖銳的線性偏振光致發光(PL)，因此NiPS3的對稱破缺磁序可以用光學技術探測。
在本論文中，我們的目的是了解改變摻雜是否會影響NiPS3的反鐵磁特性。為此，我們製造了NiPS3場效電晶體。電傳輸測量表明NiPS3是n型摻雜，並且通過掃描閘極電壓能有效地調整材料的費米能階。在此基礎上，我們進一步研究了 NiPS3 PL的強度和線性二向色性與施加閘極電壓之間的關係。結果清楚地揭示了當NiPS3調整為n摻雜時，其PL強度會降低而線性偏振度則會增加，這些表明了對二維反鐵磁性進行電控制的可能性。

The 2D antiferromagnetic material NiPS3 has recently attracted great attentions. This is because NiPS3 exhibits strong magnetic-excitons coupling, which leads to ultra-sharp linearly polarized photoluminescence (PL). The symmetry breaking magnetic order of NiPS3 can be probed by using the optical technique.
In this thesis, our aim is to understand whether varying the doping of NiPS3 would affect its antiferromagnetic properties. To achieve this, we fabricate a NiPS3 field effect transistor. Our electrical transport measurement indicates that NiPS3 is N-doped and its Fermi level can be effectively tuned by sweeping the gate voltages. Built on this foundation, we further investigate the PL intensity and linear dichroism of NiPS3 as a function of applied gate voltages. Our results clearly unveil that when tuning NiPS3 into N-doped, its PL intensity (degree of linear polarization) would decrease (increase). These suggest the possibility of electric control of the 2D antiferromagnetism.

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