EAGER: The Fundamentals of Exotic Exciton Complexes in 2D Janus Semiconductors

Janus晶体以罗马双面神命名，是一种新型的超薄二维材料。在这里，‘’Janus‘’这个名字源于古罗马的起源和过渡之神，它有两张脸，一张面向未来，另一张面向过去。与Janus本人类似，Janus材料在纳米尺度上有两个不同的面和两个不同的原子排列。该理论告诉我们，这些材料具有相当非凡的光学、电学和磁性，并在量子工程、量子光学和自旋电子学等领域展示了新技术的前景。但由于样品制备和测量技术的限制，我们对这些材料的了解仅限于理论，没有任何实验上的见解。该项目旨在使用令人印象深刻的合成和表征技术来了解Janus晶体的光学性质。下一步，它将采取措施将它们与其他量子平台集成，以实现下一代光学量子应用。在这样做的同时，教育工作为亚利桑那州立大学的材料沉积/生长实验室创造了全新的实验室之旅，面向潜在的K-12学生。该项目旨在研究过渡后金属硫化物2D Janus层的光学性质，并将它们与微腔集成，以稳定复杂的激子络合物，用于新型量子应用。最初的实验集中在合成外延级和激子级2D Janus晶体，并通过最先进的显微镜和光谱表征技术来确定它们的光学性质。我们的目标是建立这些材料的基本激子行为，如激子系列，激子结合能，偶极-偶极激子，以及当镜像对称性被打破时，层中存在巨大的偏振时的寿命。一旦建立，更多的研究集中在当这些2D Janus层与DBR微腔集成时，玻色凝聚体或丰富的激子复合体的形成和理解。如果成功，该项目将为这些新的量子材料提供第一批实验洞察力。这项研究也为量子探测器、传感器和电谷电子学的众多应用的发展铺平了道路。首席调查员继续致力于在大学内部以及与凤凰城初中和高中、太阳魔鬼日和开放日活动以及技术实验室培训和参观活动进行外展、教育和合作努力。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Named after the two-faced Roman god, Janus crystals are a new class of ultrathin two-dimensional materials. Here, the name ''Janus'' originates from the ancient Roman God of beginnings and transitions with two faces one looking to the future while the other facing to the past. Similar to Janus himself, Janus materials have two different faces with two different atomic arrangement at the nanoscale. The theory tells us that these materials have rather extraordinary optical, electrical, and magnetic properties and show promise towards new technologies in quantum engineering, quantum optics, and spintronics. But our understanding of these materials are only limited to theory without any experimental insights due to limitations in sample preparation and measurement techniques. This project aims understanding the optical properties of Janus crystals using impressive synthesis and characterization techniques. Next, it takes steps to integrate them with other quantum platforms for next generation optical quantum applications. While doing so, the educational efforts create completely new lab tours to material deposition / growth labs at Arizona State University for prospective K-12 students.The project aims to investigate optical properties of post-transition metal chalcogenide 2D Janus layers and integrate them with microcavities to stabilize complex exciton complexes for new type of quantum applications. The initial experiments focus on the synthesis of epitaxial and excitonic grade 2D Janus crystals and establishing their optical properties through the state-of-the-art microscopy and spectroscopy characterization techniques. The goal is to establish the fundamental excitonic behavior of these materials such as excitonic series, exciton binding energies, dipolar-dipolar excitons, and lifetimes when the mirror symmetry is broken and large colossal polarization is present in the layer. Once established, additional studies focus on formation and understanding of Bose condensates or rich exciton complexes when these 2D Janus layers are integrated with DBR microcavities. If successful, the project provides the very first experimental insights into these new class of quantum material. This study also paves the way for development of numerous applications of quantum detectors, sensors, and valleytronics. The principal investigator continues to be committed to outreach, education and collaborative efforts within the university as well as with Phoenix middle and high schools, Sun Devil Days and Open House events and technical laboratory training and tours.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.