ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Lasing in active, sub-mean-free path-sized systems with dense, random, weak scatterers

Prasad, Raghavendra B and Ramachandran, Hema and Sood, Ajay Kumar and Subramanian, CK and Kumar, Narendra (1997) Lasing in active, sub-mean-free path-sized systems with dense, random, weak scatterers. In: Applied Optics Appl Optic, 36 (30). pp. 7718-7724.

[img] PDF
Lasing_in.pdf - Published Version
Restricted to Registered users only

Download (285kB) | Request a copy
Official URL: http://www.opticsinfobase.org/abstract.cfm?URI=ao-...


We report enhanced emission and gain narrowing in Rhodamine 590 perchlorate dye in an aqueous suspension of polystyrene microspheres. A systematic experimental study of the threshold condition for and the gain narrowing of the stimulated emission over a wide range of dye concentrations and scatterer number densities showed several interesting features, even though the transport mean free path far exceeded the system size. The conventional diffusive-reactive approximation to radiative transfer in an inhomogeneously illuminated random amplifying medium, which is valid for a transport mean-free path much smaller than the system size, is clearly inapplicable here. We propose a new probabilistic approach for the present case of dense, random, weak scatterers involving the otherwise rare and ignorable sub-mean-free-path scatterings, now made effective by the high gain in the medium, which is consistent: with experimentally observed features. (C) 1997 Optical Society of America.

Item Type: Journal Article
Publication: Applied Optics Appl Optic
Publisher: Optical Society of America
Additional Information: Copyright of this article belongs to Optical Society of America.
Keywords: Random-amplifying medium;lasing;sub-mean-free path.
Department/Centre: Division of Physical & Mathematical Sciences > Physics
Date Deposited: 18 Oct 2011 04:35
Last Modified: 18 Oct 2011 04:35
URI: http://eprints.iisc.ac.in/id/eprint/38284

Actions (login required)

View Item View Item