Alexey G. Yamilov

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We present a numerical study of lasing modes in diffusive random media with local pumping. The reabsorption of emitted light suppresses the feedback from the unpumped part of the sample and effectively reduces the system size. The lasing modes are dramatically different from the quasi modes of the passive system (without gain or absorption). Even if all the(More)
X. Wu, W. Fang, A. Yamilov, A. A. Chabanov, A. A. Asatryan, L. C. Botten, and H. Cao Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA Department of Physics, University of Missouri-Rolla, Rolla, Missouri 65409, USA Department of Physics and Astronomy, University of Texas-San Antonio, San Antonio, Texas 78249, USA(More)
We show that the recently developed self-consistent theory of Anderson localization with a positiondependent diffusion coefficient is in quantitative agreement with the supersymmetry approach up to terms of the order of 1 /g0 2 with g0 the dimensionless conductance in the absence of interference effects and with large-scale ab initio simulations of the(More)
This work presents results of ab-initio simulations of continuous wave transport in disordered absorbing waveguides. Wave interference effects cause deviations from diffusive picture of wave transport and make the diffusion coefficient position- and absorption-dependent. As a consequence, the true limit of a zero diffusion coefficient is never reached in an(More)
We studied numerically and experimentally the effects of structural disorder on the performance of ultraviolet photonic crystal slab lasers. Optical gain selectively amplifies the high-quality modes of the passive system. For these modes, the in-plane and out-of-plane leakage rates may be automatically balanced in the presence of disorder. The spontaneous(More)
We present direct experimental evidence for position-dependent diffusion in open random media. The interference of light in time-reversed paths results in renormalization of the diffusion coefficient, which varies spatially. To probe the wave transport inside the system, we fabricate two-dimensional disordered waveguides and monitor the light intensity from(More)
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(More)
Theoretical modeling and laboratory tests are conducted for nonlinear auto-oscillating piezoelectric ultrasonic devices coupled to reverberant elastic bodies. The devices are shown to exhibit behavior familiar from the theory of coupled auto-oscillators. In particular, these spontaneously emitting devices adjust their limit-cycle frequency to the spectrum(More)
We introduce a numerical recipe for calculating the density of the resonant states of the clusters of dielectric spheres. Using truncated multipole expansions ~generalized multisphere Mie solution! we obtain the scattering matrix of the problem. By introducing an infinitesimal absorption in the spheres we express the dwell time of the electromagnetic wave(More)