Abstract
Active control of the spatial pump profile is proposed to exercise control over random laser emission. We demonstrate numerically the selection of any desired lasing mode from the emission spectrum. An iterative optimization method is employed, first in the regime of strong scattering where modes are spatially localized and can be easily selected using local pumping. Remarkably, this method works efficiently even in the weakly scattering regime, where strong spatial overlap of the modes precludes spatial selectivity. A complex optimized pump profile is found, which selects the desired lasing mode at the expense of others, thus demonstrating the potential of pump shaping for robust and controllable single mode operation of a random laser.
- Received 20 February 2012
DOI:https://doi.org/10.1103/PhysRevLett.109.033903
© 2012 American Physical Society
Focus
How to Control a Random Laser
Published 20 July 2012
Simulations show that a new technique can control the wavelength of a random laser—a type of laser that lacks mirrors and whose output has been impossible to control.
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