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arXiv · 2001.11126

Strain-induced tuning of optical properties of layered Mo$S_2$

Shubham Bhagat·Shivani Sharma·Jasvir Singh·Sandeep Sharma
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Abstract

The sensitive correlation between optical parameters and strain in Mo$S_2$ results in a totally different approach to tune the optical properties. Usually, an external source of strain is employed to monitor the optical and vibrational properties of a material. It is always challenging to have a precise control over the strain and its consequences on material properties. Here, we report the presence of a compressive strain in Mo$S_2$ crystalline powder and nanosheets obtained via the process of ball-milling and probe sonication. The diffraction peaks in the X-ray diffraction pattern shift to higher 2$\theta$ value implying a compressive strain that increases with the processing time. The absorption spectra, photoluminescence and Raman modes are blue-shifted w.r.t the bulk unprocessed sample. The observed blue-shift is attributed to the presence of compressive strain in the samples. Whereas in thin nano-sheets of Mo$S_2$, it is very likely that both quantum confinement as well as strain result in the observed blue-shift. These results indicate that by optimizing the processing conditions and/or time, a strain of desired amount and hence tunable shift in optical properties of material can be achieved.

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Shubham Bhagat, Shivani Sharma, Jasvir Singh, Sandeep Sharma. 2020-01-29. Strain-induced tuning of optical properties of layered Mo$S_2$. https://arxiv.org/abs/2001.11126

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