2D Materials for Optics, Excitonic and Nano-mechanical Devices
Dr Yuerui (Larry) Lu
Nano-Electro-Mechanical System (NEMS) Lab, ANU College of Engineering & Computer Science, Canberra
3:30 pm, Friday, 12 June 2015, EN515 Lecture Theatre (EN Building), Hawthorn
Two-dimensional (2D) materials have become very important building blocks for electronic, photonic, and phononic devices. The 2D material family has four key members, including the metallic graphene, transition metal dichalcogenide (TMD) layered semiconductors, semiconducting black phosphorous, and the insulating h-BN. Owing to the strong quantum confinements and defect-free surfaces, these atomically thin layers have offered us perfect platforms to investigate the interactions among photons, electrons and phonons. The unique interactions in these 2D materials are very important for both scientific research and application engineering.
In this talk, I would like to briefly summarize and highlight the key findings, opportunities and challenges in this field. Next, I will introduce/highlight our recent achievements. We demonstrated atomically thin micro-lens and gratings using 2D MoS2, which is the thinnest optical component around the world. These devices are based on our discovery that the elastic light-matter interactions in high-index 2D materials is very strong. Also, I would like to introduce a new two-dimensional material phosphorene. Phosphorene has strongly anisotropic optical response, which creates 1D excitons in a 2D system. The strong confinement in phosphorene also enables the ultra-high trion (charged exciton) binding energies, which have been successfully measured in our experiments. Finally, I would like to introduce our recent work on atomically thin mechanical resonators, which is a fantastic platform to investigate the fundamental opto-mechanical interactions and would enable ultra-precise sensing applications.