## Theory of the optical absorption of light carrying orbital angular momentum by semiconductors

##### Authors
Quinteiro, G. F.
Tamborenea, P. I.
##### Description
We develop a free-carrier theory of the optical absorption of light carrying orbital angular momentum (twisted light) by bulk semiconductors. We obtain the optical transition matrix elements for Bessel-mode twisted light and use them to calculate the wave function of photo-excited electrons to first-order in the vector potential of the laser. The associated net electric currents of first and second-order on the field are obtained. It is shown that the magnetic field produced at the center of the beam for the $\ell=1$ mode is of the order of a millitesla, and could therefore be detected experimentally using, for example, the technique of time-resolved Faraday rotation.
Comment: Submitted to Phys. Rev. Lett. (23 Jan 2008)
##### Keywords
Condensed Matter - Other Condensed Matter