On-chip Tunable Nanoemitters in a Gated Plasmonic Heterostructure and Its Future Prospects

Yu-Jung Lu^1,2*

¹RCAS, Academia Sinica, Taipei, Taiwan
²Physics, National Taiwan University, Taipei, Taiwan

* Presenter:Yu-Jung Lu, email:yujunglu@gate.sinica.edu.tw

Controlling light emission of quantum emitters, such as semiconductor quantum dots, is a central theme of nanotechnology. Typically, the emitted power from an array of quantum emitters is modulated by changing the optical or electrical pump intensity, within a given nanostructured environment. In this work, we propose and demonstrate a conceptually different approach to dynamically control the power radiated by the emitter. We experimentally demonstrate the modulation of the radiative emission rate, the emitted power, and the quantum efficiency, at constant optical pump intensity via dynamical changes to the local density states. The local density of states is modulated by changing the carrier density, under field effect gate control, in a plasmonic titanium nitride thin layer nearby the emitters. Our proof-of-principle experiment, which uses a TiN/SiO2/Ag plasmonic heterostructure, demonstrates a new active plasmonic mechanism for modulating visible light emission that is extensible to other type of emitters like 2D materials. Moreover, it also may pave a way towards ultrathin LCD-free displays with long durability, reduced pixel size and large viewing angle. In this talk, the detail working mechanisms and the outlook for gate tunable on-chip light source will be discussed. In the end, I will talk about my recent work on the ultrafast pump-probe transient absorption microscopy.

Keywords: Tunable, Plasmonic, Active devices, Quantum dots, TiN