Abstract
Optical conductivity plays an important role in characterizing the optoelectronic properties of two-dimensional materials. Here we derive the complex optical conductivities for monolayer and few-layered MoS2films from their reflectance and transmittance responses. We show that the excitonic quantum confinement effect significantly modifies both the peak energy and magnitude of their optical conductivity, manifested by a gradual blueshift in energy (consistent with two well-known models for quantum well systems) and exponential attenuation in magnitude with decreasing layer number. More importantly, the C excition induced optical conductivity peak exhibits the strongest dependence on the MoS2layer number because of its largest Bohr radius among the A, B and C excitons. This unambiguously confirms the strong influence of quantum confinement effect in the optical conductivity of MoS2, shedding important insights into understanding its rich exciton-related optical properties and therefore facilitating potential applications in optoelectronic devices.
Original language | English |
---|---|
Pages (from-to) | 8822-8828 |
Number of pages | 7 |
Journal | Journal of Materials Chemistry C |
Volume | 4 |
Issue number | 37 |
DOIs | |
Publication status | Published - 1 Jan 2016 |
ASJC Scopus subject areas
- General Chemistry
- Materials Chemistry