Ms Wang Zhuo, a PhD candidate from the NUS Graduate School for Integrative Sciences and Engineering (NGS) and first author of the paper, explained, “This is the first work to demonstrate the use of gold plasmonic nanostructures to improve the photoluminescence of tungsten diselenide, and we have managed to achieve an unprecedented enhancement of the light absorption and emission efficiency of this nanomaterial.”
Elaborating on the significance of the novel method, Prof Wee said, “The key to this work is the design of the gold plasmonic nanoarray templates. In our system, the resonances can be tuned to be matched with the pump laser wavelength by varying the pitch of the structures. This is critical for plasmon coupling with light to achieve optimal field confinement.”
The novel research was first published online in the journal Nature Communications on 6 May 2016.
The next step
The novel method developed by the NUS team, in collaboration with researchers from the Singapore University of Technology and Design and Imperial College, opens up a new platform for investigating novel electrical and optical properties in the hybrid system of gold with tungsten diselenide. Moving forward, the research team will further investigate the effectiveness of the lateral gold plasmon in enhancing the second harmonic generation and electroluminescence of TMDCs. They will also investigate these effects in other two dimensional transition metal dichalcogenides with different band gaps, as they are expected to show different interaction mechanisms.