Collaborative Research: Plasmonic lasing with two-dimensional heterostructures in the intrinsic regime

非技术性描述：一类新的原子级薄材料，即所谓的二维半导体，作为用于诸如激光器和发光二极管的光电器件的可行材料，已经引起了相当大的兴趣。先前的研究报告指出，这些新材料受到有害的环境相互作用和材料缺陷的影响，导致发光效率低，从而阻碍了实际应用。该项目最终能够提高纳米激光等纳米级光源以及新型量子光源的效率和性能，这些光源是即将到来的技术所需的，这些技术使用光而不是电子来直接在半导体芯片上实现密集集成的信息处理。该研究方法利用了一种很有前途的晶体生长技术，导致二维材料中的缺陷密度非常低。该研究还将这些材料与光学设备集成，可以将光聚焦到极小的斑点中，从而大大提高这些半导体的发光效率。教育活动包括接触代表性不足的群体，以及在材料生长，洁净室制造和光学表征方面培训下一代科学家和工程师，并通过将新的基于研究的教育材料引入研究生课程。技术说明：单层过渡金属二硫属化物是半导体材料，其在光电和谷电子应用中获得了相当大的兴趣，但是经常发现其遭受导致低量子效率的环境相互作用和材料缺陷。该项目将具有超低无序环境的二维异质结构与低群速度等离子体带边模式相结合，以研究具有高方向性输出的片上纳米激光器的激光和量子相干特征。本计画进一步探讨闸极可调激子与三重子增益，并实现在珀塞尔范围内与等离子体能隙模式深度耦合的确定性定位量子发射器。该研究方法结合了材料生长，2D组装和纳米纤维，以实现片上光子学和量子信息科学领域的变革性进展，旨在促进“本质清洁”2D半导体的出色光学特性。与等离子体纳米腔的集成提供了令人兴奋的新的进展，直接定制的光-物质相互作用的珀塞尔和强耦合制度。最终，该项目能够提高片上纳米激光器的效率和性能，用于集成到光学电路中，以及量子信息科学所需的单光子源;这些都受到激子量子物理学的影响，并显著受益于低无序环境，减少通量生长材料中的材料缺陷，以及等离子体耦合，以直接增加量子产率。该项目还提出了一个推广模式，重点是与哥伦比亚数学、科学和工程中学建立长期关系，这是一所公立的6-12岁学校，主要是西班牙裔和非洲裔美国学生。对代表性不足的群体的推广活动将利用史蒂文斯与工程项目中的妇女和工程少数民族国家行动理事会（NACME）等组织的机构联系。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

Nontechnical description: A new class of atomically thin materials, so called two dimensional semiconductors, has gained considerable interest as a viable material for optoelectronic devices such as lasers and light emitting diodes. Previous research reports that these new materials suffer from detrimental environmental interactions and material defects that result in low light emission efficiencies, thereby impeding practical applications. This project ultimately enables an efficiency and performance boost for nanoscale light sources such as nanolasers as well as novel quantum light sources that are required in upcoming technologies that use light instead of electrons to realize densely integrated information processing directly on a semiconductor chip. The research approach utilizes a promising crystal growth technique that leads to very low defect densities in two dimensional materials. The research also integrates these materials with optical devices that can focus the light into extremely small spots, leading to drastically enhanced light emission efficiency from these semiconductors. The educational activities include reaching out to underrepresented groups as well as training the next generation of scientists and engineers in materials growth, clean-room fabrication and optical characterization, and through introducing new research-based educational materials into the graduate curriculum. Technical description: Monolayer transition metal dichalcogenides are semiconductor materials that have gained considerable interest for optoelectronic and valleytronic applications but are often found to suffer from environment interactions and material defects that lead to low quantum efficiencies. This project integrates two-dimensional heterostructures featuring ultralow-disorder environments with low-group-velocity plasmonic band-edge modes in order to investigate lasing and quantum coherence signatures of on-chip nanolasers with highly-directional output. This project furthermore explores gate-tunable exciton and trion gain and realizes deterministic positioned quantum emitters coupled to plasmonic gap modes deeply in the Purcell regime. The research approach combines material growth, 2D assembly, and nanofabrication to enable transformative advances for the field of on-chip photonics and quantum information science that aims to facilitate the outstanding optical properties of "intrinsically-clean" 2D semiconductors. The integration with plasmonic nanocavities offers exciting new inroads to directly tailor the light-matter interaction in the Purcell and strong-coupling regime. Ultimately, this project enables an efficiency and performance boost for on-chip nanolasers for the integration in optical circuits, as well as for single-photon sources required for quantum information science; these are all affected by the exciton photophysics and significantly benefit by low-disorder environments, reduced material defects in flux-grown material, and plasmonic coupling to directly increase the quantum yield. The project also puts forth an outreach model that focusses on building long-term relationships with the Columbia Secondary School for Math, Science, and Engineering, a public, 6-12 school with a predominant Hispanic and African-American student population. Outreach activities to under-represented groups will leverage Stevens' institutional affiliations with organizations such as the Women in Engineering Program and the National Action Council for Minorities in Engineering (NACME).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.