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arXiv · 1812.05543

Suppression of the Shear Raman Mode in Defective Bilayer MoS2

Pierce Maguire·Clive Downing·Jakub Jadwiszczak·Maria O'Brien·Darragh Keane·John B. McManus·Georg S. Duesberg·Valeria Nicolosi·Niall McEvoy·Hongzhou Zhang
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Abstract

We investigate the effects of lattice disorders on the low frequency Raman spectra of bilayer MoS2. The bilayer MoS2 was subjected to defect engineering by irradiation with a 30 keV He+ ion beam and the induced morphology change was characterized by transmission electron microscopy. With increasing ion dose the shear mode is observed to redshift and it is also suppressed sharply compared to other Raman peaks. We use the linear chain model to describe the changes to the Raman spectra. Our observations suggest that crystallite size and orientation are the dominant factors behind the changes to the Raman spectra.

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Pierce Maguire, Clive Downing, Jakub Jadwiszczak, Maria O'Brien, Darragh Keane, John B. McManus, Georg S. Duesberg, Valeria Nicolosi, Niall McEvoy, Hongzhou Zhang. 2018-12-14. Suppression of the Shear Raman Mode in Defective Bilayer MoS2. https://doi.org/10.1063/1.5086366

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