Optical and dielectric properties of novel electronic materials using Shimadzu UV-3600 Plus

We are interested in the growth of new materials and investigate physical properties affected by size, chemical doping, interface, heterostructure, and external tuning parameters (light, magnetic field, etc.).

We are particularly interested in understanding the optical and dielectric properties of novel electronic materials that are fabricated in our lab in thin film form. Since the discovery of graphene, Transition metal dichalcogenides (TMDs) have merged as one of the most exciting systems to investigate properties at the nanoscale. In our lab, we have developed few-layer large-area MoS2 thin-films using a PVD-CVD growth process that can produce films with tunable properties [1]. For this talk, I will specifically focus on their broadband dielectric properties measured using Shimadzu UV3600 Plus [2]. Next, I will discuss our work on the influence finite-size in Topological insulator Bi2Se3 thin-films. Through a combination of quantum confinement and Burstein-Moss effect, we discovered a large optical blue-shift in Bi2Se3 as it approaches the 2D limit [3].

References

1. Viable route towards large-area two dimensional MoS2 using magnetron sputtering, H. Samassekou, A. Alkabsh, M. Wasala, M. Eaton, A. Walber, A. Walker, O. Pitkänen, K. Kordas, S. Talapatra, T.Jayasekera, Dipanjan Mazumdar, 2D Materials 4 021002 (2017).

2. Broadband optical properties and electronic band structure of few-layer MoS2, Asma Alkabsh and Dipanjan Mazumdar, (unpublished) 2020.

3. Optical evidence for blue shift in Topological insulator Bismuth selenide in the few-layer limit , Yub Raj Sapkota, Asma Alkabsh, Aaron Walber, Hassana Samassekou, Dipanjan Mazumdar, Applied Physics Letters, 110, 181901 (2017).