博士生陈俊荧同学在国际物理权威期刊Applied Physics Letters上发表论文

      近日，课题组成员陈俊荧同学在刘老师的指导下，以第一作者在国际物理权威期刊《应用物理快报》(Applied Physics Letters上发表题为 “Spin Chain Orientation and Magneto-Optical Coupling in Twisted NiPS₃ Homostructures”(转角NiPS₃结构中的自旋链取向与磁光耦合效应的研究, Editor's Pick, Cover image)的实验论文。

图：转角NiPS₃结构中的自旋链取向与磁光耦合效应的研究

APL COVER IMAGE

       近年来，由于其独特的性质和在电子学、光子学和磁学中的潜在应用，二维(2D)材料的探索和理解呈现出迅猛发展势头。其中，二维磁性材料因其在超薄器件中集成自旋电子功能的潜力而受到广泛关注。镍磷三硫化物(NiPS₃)作为一种特别有前途的候选材料，因其层状结构和反铁磁(AFM)有序所展现出的有趣磁学和光学特性而备受瞩目。作为过渡金属硫化磷酸盐家族的一员，NiPS₃以其准二维层状结构而著称。这些材料通常形成范德华层状化合物，弱的层间相互作用使其易于剥离成少层或单层形式。NiPS₃晶体属于单斜结构，在其约150K的尼尔温度以下表现出AFM有序。NiPS₃中的AFM有序为XXZ型，具有面内各向异性，并且在晶格的ab面上以锯齿状AFM链耦合。理解NiPS₃中磁有序与光学特性的耦合对于开发新型光电和自旋电子器件至关重要。二维材料中激子和磁有序之间的相互作用可以导致磁光效应等独特现象，这对于包括磁传感器、存储器件和量子计算在内的应用具有关键意义。

        在本研究中，我们报道了在低温(1.65K)下观察到NiPS₃光致发光(PL)谱中的独特激子峰。这些激子峰在不同温度和功率依赖性下进行了分析，揭示了关于材料电子结构及其磁有序影响的关键信息。此外，通过测量激子和AFM有序耦合引起的PL线性偏振，量化了偏振度及其随温度和磁场的变化。通过在z轴上施加外部磁场进一步探索了NiPS₃的磁特性，观察到激子PL偏振角的显著变化，突显了NiPS₃中强磁光耦合。在不同磁场下拉曼模的调制也凸显了材料对磁扰动的敏感性，提供了对自旋-声子耦合机制的深入理解。这些发现不仅展示了NiPS₃中激子-磁有序耦合的丰富物理现象，还为基于二维磁性材料开发先进光电和自旋电子器件铺平了道路。

文章链接：https://pubs.aip.org/aip/apl/article-abstract/125/11/113102/3311822/Spin-chain-orientation-and-magneto-optical?redirectedFrom=fulltext

Comments:

The paper titled "Spin Chain Orientation and Magneto-Optical Coupling in Twisted NiPS₃ Homostructures" presents a thorough investigation into the magneto-optical properties of few-layer NiPS₃ and its twisted heterostructures, emphasizing the exploration of novel optical phenomena at cryogenic temperatures. The authors successfully demonstrate the emergence of sharp exciton peaks at low temperatures, and their detailed analysis of spin chain orientation through polarization-dependent exciton PL intensity provides significant insights into the magnetic characteristics of NiPS₃.

The study's revelation of the pronounced magneto-optical effect in fewer-layered NiPS₃, particularly the modulation of the polarization angle of exciton PL spectra under an applied magnetic field, is a noteworthy contribution to the field. This work also highlights the substantial changes observed in the polarization-dependent Raman spectrum of NiPS₃ under magnetic influence, further elucidating the interplay between magnetic order and optical properties in these materials.

In summary, this paper makes a substantial contribution to the field of 2D magnetic materials by elucidating the magneto-optical properties of NiPS₃. The methodologies are sound, the findings are significant, and the potential applications are well-articulated. I look forward to seeing further developments based on this promising research.