Effects of spatially nonuniform gain on lasing modes in weakly scattering random systems
نویسندگان
چکیده
Jonathan Andreasen,1,* Christian Vanneste,2 Li Ge,1 and Hui Cao1,3 1Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA 2Laboratoire de Physique de la Matière Condensée, CNRS UMR 6622, Université de Nice-Sophia Antipolis, Parc Valrose, F-06108 Nice Cedex 02, France 3Department of Physics, Yale University, New Haven, Connecticut 06520, USA (Received 27 October 2009; published 15 April 2010)
منابع مشابه
Creation of new lasing modes with spatially nonuniform gain.
We report on the creation of new lasing modes with spatially nonuniform profiles of optical gain in a one-dimensional random structure. It is demonstrated numerically that even without gain saturation and mode competition, the spatial nonuniformity of gain can cause dramatic and complicated changes. New lasing modes appear with frequencies between those of the lasing modes with uniform gain. We...
متن کاملStatistical studies of random-lasing modes and amplified spontaneous-emission spikes in weakly scattering systems
We measured the ensemble-averaged spectral correlation functions and statistical distributions of spectral spacing and intensity for lasing modes in weakly scattering systems, and compared them to those of the amplified spontaneous-emission spikes. Their dramatic differences illustrate distinct physical mechanisms. Our numerical simulation revealed that even without reabsorption the number of p...
متن کاملInherent stochastic linearization of random laser modes
Weakly scattering random lasers exhibit lasing modes that spatially overlap and can interact strongly via gain saturation. Consequently, lasing in highthreshold modes may be suppressed by strong low-threshold lasing modes. We numerically examine the effect of inherent spontaneous emission noise on this strong nonlinear phenomenon. With a method to incorporate this noise into the Maxwell–Bloch e...
متن کاملEffect of local pumping on random laser modes in one dimension
We have developed a numerical method based on the transfer matrix to calculate the quasi modes and lasing modes in one-dimensional random systems. Depending on the relative magnitude of the localization length versus the system size, there are two regimes in which the quasi modes are distinct in spatial profile and frequency distribution. In the presence of uniform gain, the lasing modes have o...
متن کاملodes of random lasers
In conventional lasers, the optical cavity that confines the photons also determines essential characteristics of the lasing modes such as wavelength, emission pattern, directivity, and polarization. In random lasers, which do not have mirrors or a well-defined cavity, light is confined within the gain medium by means of multiple scattering. The sharp peaks in the emission spectra of semiconduc...
متن کامل