Abstract
Graphene can be rendered semiconducting via energy gaps introduced in a variety of ways, e.g., coupling to substrates, electrical biasing, or nanostructuring. To describe and compare different realizations of gapped graphene we propose a simple two-band model in which a "mass" term is responsible for the gap. The optical conductivity predicted for this model is obtained as a simple closed-form expression. In addition, analytical estimates for the binding energy of excitons are derived and the impact of excitons on the optical response is analyzed.
Original language | English |
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Journal | Physical Review B. Condensed Matter and Materials Physics |
Volume | 79 |
Issue number | 11 |
Pages (from-to) | 113406 |
ISSN | 0163-1829 |
DOIs | |
Publication status | Published - 2009 |
Bibliographical note
Copyright 2009 American Physical SocietyKeywords
- energy gap
- binding energy
- nanostructured materials
- elemental semiconductors
- carbon
- excitons
- optical conductivity