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arXiv · 1010.6047

Electronic states and optical properties of PbSe nanorods and nanowires

A. C. Bartnik·Al. L. Efros·W. -K. Koh·C. B. Murray·F. W. Wise
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Abstract

A theory of the electronic structure and excitonic absorption spectra of PbS and PbSe nanowires and nanorods in the framework of a four-band effective mass model is presented. Calculations conducted for PbSe show that dielectric contrast dramatically strengthens the exciton binding in narrow nanowires and nanorods. However, the self-interaction energies of the electron and hole nearly cancel the Coulomb binding, and as a result the optical absorption spectra are practically unaffected by the strong dielectric contrast between PbSe and the surrounding medium. Measurements of the size-dependent absorption spectra of colloidal PbSe nanorods are also presented. Using room-temperature energy-band parameters extracted from the optical spectra of spherical PbSe nanocrystals, the theory provides good quantitative agreement with the measured spectra.

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A. C. Bartnik, Al. L. Efros, W. -K. Koh, C. B. Murray, F. W. Wise. 2010-10-28. Electronic states and optical properties of PbSe nanorods and nanowires. https://doi.org/10.1103/physrevb.82.195313

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