講演情報
[15p-K207-5]Quantum emission from interface excitons in mixed-dimensional heterostructures
〇Nan Fang1, Yih-Ren Chang1, Shun Fujii1,2, Daiki Yamashita1,3, Mina Maruyama4, Yanlin Gao4, Chee Fai Fong1, Daichi Kozawa1,5, Keigo Otsuka1,6, Kosuke Nagashio6, Susumu Okada4, Yuichiro Kato1 (1.RIKEN, 2.Keio Univ., 3.AIST, 4.Univ. of Tsukuba, 5.NIMS, 6.UTokyo)
キーワード：
carbon nanotube、tungsten diselenide、mixed-dimensional heterostructure
Two-dimensional van der Waals heterostructures have unveiled unconventional phenomena that emerge at atomically precise interfaces, and further advancements are anticipated in mixed-dimensional heterostructures. In this study, we explore exciton physics within 1D-2D heterostructures consisting of one-dimensional carbon nanotubes and two-dimensional tungsten diselenide. An anthracene-assisted transfer technique is utilized to form the clean and free-standing heterostructures. Both the chirality and the layer number are identified before assembling, allowing for precise engineering of the band alignment. For example, in the small band gap nanotube heterostructures, type I band alignment is formed and exciton transfer is observed.
For large band gap nanotubes corresponding to type II band alignment, exciton transfer diminishes whereas bright emission peaks originating from the interface are identified. We assign the peaks to interface excitons as they only appear in type-II heterostructures. Localization of low-energy interface excitons is indicated by extended lifetimes as well as small excitation saturation powers, and photon correlation measurements confirm room-temperature quantum emission. The observation of interface excitons as room-temperature quantum emitters at telecommunication bands opens up new opportunities for applications in quantum technologies and optoelectronics.
For large band gap nanotubes corresponding to type II band alignment, exciton transfer diminishes whereas bright emission peaks originating from the interface are identified. We assign the peaks to interface excitons as they only appear in type-II heterostructures. Localization of low-energy interface excitons is indicated by extended lifetimes as well as small excitation saturation powers, and photon correlation measurements confirm room-temperature quantum emission. The observation of interface excitons as room-temperature quantum emitters at telecommunication bands opens up new opportunities for applications in quantum technologies and optoelectronics.