IFIBA   22255
INSTITUTO DE FISICA DE BUENOS AIRES
Unidad Ejecutora - UE
artículos
Título:
Below-bandgap excitation of bulk semiconductors by twisted light
Autor/es:
G. F. QUINTEIRO
Revista:
EUROPHYSICS LETTERS
Editorial:
EPL ASSOCIATION
Referencias:
Año: 2010 vol. 91 p. 27002 - 27002
ISSN:
0295-5075
Resumen:
I theoretically investigate the excitation of bulk semiconductors 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 momentum of light. I predict that the optical
excitation produces a superposition of exciton-like states that undergo
a complex center-of-mass motion. In addition, I show that the energy at
which the absorption occurs is slightly different from that of pure
excitons, due to the center-of-mass kinetic energy of the new states.
Finally, I provide expressions for the induced polarization and
electric current, which exhibit complex spatial patterns that mimic the
twisted-light electric field.