학술논문

Effective mass theory for the anisotropic exciton in 2D crystals: Application to phosphorene
Document Type
Working Paper
Source
Phys. Rev. B 91, 245421 (2015)
Subject
Condensed Matter - Mesoscale and Nanoscale Physics
Language
Abstract
We present a theoretical study of the exciton binding energy for anisotropic two-dimensional crystals. We obtain analytical expressions from variational wave functions in different limits of the screening length to exciton size ratio and compare them with numerical solutions, both variational and exact. As an example, we apply these results to phosphorene, a monolayer of black phosphorous. Aided by density functional theory calculations for the evaluation of the two-dimensional polarizability, our analytical solution for the exciton binding energy gives a result which is very close to the numerical ones and, in turn, is comparable to the experimental value, as recently reported.
Comment: 9 pages, 11 figures. v2 is the published version (in PRB) plus some extra small details, and corrected factor of 2 in the y-axis of Fig. 6!! Important corrections with respect to previous cond-mat version: Fig. 2, Fig. 3, Fig. 6, and extra details in the captions of Section IV