Related papers: Loss-induced lasing: new findings in laser theory?
The statistical properties of three-level lasing are investigated theoretically. It is assumed that the three-level medium is coherently excited by another laser with an arbitrary photon statistics. It is proved that, under the specific…
The mode dynamics of a random laser is investigated in experiment and theory. The laser consists of a ZnCdO/ZnO multiple quantum well with air-holes that provide the necessary feedback. Time-resolved measurements reveal multimode spectra…
Exceptional points, with simultaneous coalescence of eigen-values and eigen-vectors, can be realized with non-Hermitian photonic systems. With the enhanced response, exceptional points have been proposed to improve the performance of…
Since the analogy between laser oscillation and second-order phase transition was indicated in the 1970s, dynamical fluctuations on lasing threshold inherent in critical phenomena have gained significant interest. Here, we numerically and…
Researchers claim to have observed superluminal (faster than light) propagation of a laser pulse in a gain medium by a new mechanism in which there is no distortion of the pulse [Nature, 406, 277 (2000)]. Our analysis shows that the…
A theoretical study of power loss from periphery of an ultrashort pulse laser beam and temporally resolved defocussing produced by laser induced plasma are performed using paraxial approximation. Our analysis incorporate consideration of…
We demonstrate experimentally a new form of induced transparency, i.e., chaos-induced transparency, in a slightly deformed microcavity which support both continuous chaotic modes and discrete regular modes with Q factors exceeding 3X?10^7.…
We show that purely lossy defects in one- and two-dimensional non-Hermitian photonic crystals can induce transmission matrix singularities not accessible with lossless defects. These singularities in turn can enable dramatic enhancement in…
Random lasers are based on disordered materials with optical gain. These devices can exhibit either intensity or resonant feedback, relying on diffusive or interference behaviour of light, respectively, which leads to either coupling or…
The genesis of lasing, as an evolution of the laser hybrid eigenstates comprised of electromagnetic modes and atomic polarization, is considered. It is shown that the start of coherent generation at the laser threshold is preceded by the…
A novel form of Ramsey narrowing is identified and characterized. For long-lived coherent atomic states coupled by laser fields, the diffusion of atoms in-and-out of the laser beam induces a spectral narrowing of the atomic resonance…
Recent numerical and theoretical studies have demonstrated that the modes at threshold of a random laser are in direct correspondence with the resonances of the same system without gain, a feature which is well known in a conventional laser…
The lasing threshold of a random laser is computed numerically from a generic model. It is shown that spatial correlations of the disorder in the medium (i.e., dielectric constant) lead to an increase of the decay rates of the eigenmodes…
In this report we study the Vernier effect in coupled laser systems consisting of two cavities. We show that depending on the nature of their coupling, not only can the "supermodes" formed at the overlapping resonances of the coupled…
In sufficiently strong scattering media, light transport is suppressed and modes are exponentially localized. Anderson-like localized states have long been recognized as potential candidate for high-Q optical modes for low-threshold, cost…
We show that under appropriate conditions the impact of a very short and intense laser pulse onto a plasma causes the expulsion of surface electrons with high energy in the direction opposite to the one of propagation of the pulse. This is…
The conventional picture of the light amplification by stimulated emission of radiation (laser) is broken under the ultrastrong interaction between the electromagnetic fields and matter, and distinct dynamics of the electric field and of…
One of the most fundamental questions in laser physics is the following: Which mode of an optical cavity will reach the lasing threshold first when gain is applied? Intuitively, the answer appears straightforward: When a particular mode is…
We discuss a class of lasing modes created by a spatially inhomogeneous gain profile. These lasing modes are "extra modes", in addition to, and very different from, conventional lasing modes, which arise from the passive cavity resonances.…
A theory of lasing in an optically thin layer of active centers disposed at a metal surface is developed from first principles. The approach is based on a rigorous account of the local field in a close vicinity of a reflective surface which…