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Register a new userBelow-bandgap excitation of bulk semiconductors by twisted light
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Added by
Guillermo Federico Quinteiro
Publication date
2013
fields
Physics
and research's language is
English
Authors
G. F. Quinteiro
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I theoretically investigate the response of bulk semiconductors to excitation by twisted light below the energy bandgap. To this end, I modify a well-known model of light-semiconductor interaction to account for the conservation of the lights momentum. I show that the excited states can be thought of as a superposition of slightly perturbed exciton states undergoing a complex center-of-mass motion. In addition, the absorption would occur at a slightly shifted energy (compared to plane waves) and would exhibit complex spatial patterns in the polarization and current.
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