Related papers: Lasing versus lasing without inversion in an optic…
We develop an analytical theory for diffusive random lasers by coupling the transport theory of the disordered medium to the semiclassical laser rate equations, accounting for (coherent) stimulated and (incoherent) spontaneous emission.…
In a recent work, using a coupled microresonator system with tailored gain and loss parameters B. Peng et al. [Science 346, 328 (2014)] have experimentally reported on an apparently counterintuitive effect in laser theory, namely the…
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 tunable and switchable multi-wavelength erbium-doped fiber ring laser based on a new type tunable comb filter is proposed and demonstrated. By adjusting the polarization controllers, dual-function operation of the channel spacing…
The approach to calculating the effective dielectric and magnetic response in bounded composite materials is developed. The method is essentially based on the renormalisation of the dielectric matrix parameters to account for the surface…
Random lasing occurs as the result of a coherent optical feedback from multiple scattering centers. Here, we demonstrate that plasmonic gold nanostars are efficient light scattering centers, exhibiting strong field enhancement at their…
A gain-assisted plasmonic waveguide with two detuned resonators is investigated in the plasmon-induced transparency window. Phase map is employed to study power transmittance and group delay for varying gain coefficients and frequency…
There is increasing interest in filling the gap of miniaturized terahertz/mid-infrared radiation sources and, particularly, in incorporating these sources into micro/nanophotonic circuits. By using rigorous electromagnetic methods, we…
Intersubband transitions in a superlattice under homogeneous electric field is studied within the tight-binding approximation. Since the levels are equi-populated, the non-zero response appears beyond the Born approximation. Calculations…
Realizing laterally continuous ultra-thin gold films on transparent substrates is a challenge of significant technological importance. In the present work, formation of ultra-thin gold films on fused silica is studied, demonstrating how…
We investigate the feasibility of UV lasing without inversion at a wavelength of $253.7$ nm utilizing interacting dark resonances in mercury vapor. Our theoretical analysis starts with radiation damped optical Bloch equations for all…
The contrasting melting behavior of different surface orientations in metals can be explained in terms of a repulsive or attractive effective interaction between the solid-liquid and the liquid-vapor interface. We show how a crucial part of…
Mirrorless lasing has been a topic of particular interest for about a decade due to promising new horizons for quantum science and applications. In this work, we review first-principles theory that describes this phenomenon, and discuss…
Optical gain is a critical process in today's semiconductor technology and it is most often achieved via stimulated emission. In this theoretical study, we find a resonant TE mode in biased low-symmetry two-dimensional metallic systems…
A solid-state organic thin-film laser with intracavity frequency doubling is reported. Tunable ultraviolet emission from 309 to 322 nm is achieved from a vertical external cavity surface-emitting organic laser, with 2 % efficiency (1 $\mu$J…
A self-consistent computational scheme is presented for one dimensional (1D) and two dimensional (2D) metamaterial systems with gain incorporated into the nanostructures. The gain is described by a generic four-level system. The loss…
We introduce a class of unidirectional lasing modes associated with the frozen mode regime of non-reciprocal slow-wave structures. Such asymmetric modes can only exist in cavities with broken time-reversal and space inversion symmetries.…
We theoretically propose directional, low-threshold plasmon lasing in both the near-infrared and visible wavelengths by utilizing spatially coherent surface plasmon polaritons on a meta-surface. The gain strength required for threshold…
Optical bistability, the basic nonlinear phenomenon mediating the control of light by light, paves the way to the all-optical logic being of ultimate demand for a plethora of applications in laser information technologies. The desirable…
The observation of photoluminescence (PL) or achieve lasing modes in alcohol solutions of dyes or other media (silica glass fibers), doped in small quantities by certain active working elements, which are dipped in the environment, do not…