Strong Interactions in Multimode Random Lasers
Hakan E. Türeci,1*
Li Ge,2
Stefan Rotter,2
A. Douglas Stone2
Unlike conventional lasers, diffusive random lasers (DRLs) have no resonator to trap light and no high-Q resonances to support lasing. Because of this lack of sharp resonances, the DRL has presented a challenge to conventional laser theory. We present a theory able to treat the DRL rigorously and provide results on the lasing spectra, internal fields, and output intensities of DRLs. Typically DRLs are highly multimode lasers, emitting light at a number of wavelengths. We show that the modal interactions through the gain medium in such lasers are extremely strong and lead to a uniformly spaced frequency spectrum, in agreement with recent experimental observations.
1 Institute of Quantum Electronics, Eidgenössische Technische Hochschule (ETH) Zurich, 8093 Zurich, Switzerland.
2 Department of Applied Physics, Post Office Box 208284, Yale University, New Haven, CT 06520–8284, USA.
Presently on leave from Technische Universitat Wien, Wiedner Hauptstraße 8-10/136, A-1040 Vienna, Austria.
* To whom correspondence should be addressed. E-mail: tureci{at}phys.ethz.ch
