Research expeditions:

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• Other experimental projects

We have been actively involved in two collaborative experimental projects within the general context of surface waves. The first one involved study of plasmonic and excitonic devices based on graphene and MoS₂ . For this purpose, we obtained extensive first hand experience in nanofabrication, including thin film deposition, focused ion beam milling, electron beam lithography and spin coating. Numerous batches of these samples were characterized using Raman, FTIR, AFM, SEM and TEM. In addition, our colleagues and I built various optical setups such as ATR, Nd:YAG laser and z-scan saturation intensity measurement system. The second project involved the study of coherent coupling between surface acoustic waves and local contact resonances of microspheres. I was attracted to this project because this mechanics problem is analogous to the problem of plasmon-exciton coupling, which I was studying simultaneously. For this project, together with a postdoc, we carried out several monolayer deposition and subsequent laser vibrometer measurement of contact resonance frequency. Subsequently, we built a grating interferometer to resolve surface acoustic waves optically. Part of this work was published in Physical Review Letters, 111:036103, 2013.

In the past, we have worked on developing a vapor-liquid-solid (VLS) deposition system for fabricating zinc oxide nanowires. These nanowires were employed for enhancing the efficiency of organic thin film transistors. This work was published in International Journal of Nanoscience, 10:761, 2011. A number of supplemental experimental techniques were optimized to accomplish this project: for eg. gold nanoparticle synthesis and UV-Visible spectroscopic characterization, wet etching of Hafnium oxide films using hydroflouric acid treatment, surface modification using self assembled monolayers (OTS and HMDS treatment), etc.