Related papers: Electrically driven random lasing from a modified …
Coherent light sources, such as free electron lasers, provide bright beams for biology, chemistry, physics, and advanced technological applications. Increasing the brightness of these sources requires progressively larger devices, with the…
A comprehensive approach for simulating lasing dynamics in a liquid crystal based laser is presented. The approach takes into account the transformation of the liquid crystal structure caused by applied voltage. In particular, it allows us…
A radiator is typically a parabolic mirror illuminated by an electromagnetic source, or a cylindrical transducer of resonant vibrations. Both of these devices are designed to radiate either a beam of parallel rays or a (focused) beam that…
We propose a feasible scenario to directly polarize a relativistic electron beam and obtain overall polarization in various directions through a filter mechanism for single-shot collision between an ultrarelativistic unpolarized electron…
We demonstrate a new practical approach for generating multicolour spiral-shaped beams. It makes use of a standard silica optical fibre, combined with a titled input laser beam. The resulting breaking of the fibre axial symmetry leads to…
Unlike traditional fiber laser with defined resonant cavity, random fiber laser (RFL), whose operation is based on distributed gain and feedback via Rayleigh scattering and stimulated Raman scattering in long passive fiber, has fundamental…
Providing artificial light and enhancing the quality of the respective light sources is of continued interest in the fields of solid state-, condensed matter, and semiconductor physics. A lot of research has been done to increase luminous…
The dynamics of a semiconductor-laser array whose individual elements are coupled in a global way through an external mirror is numerically analysed. A coherent in-phase solution is seen to be preferred by the system at intermediate values…
We review principles and trends in the use of semiconductor nanowires (NWs) as gain media for stimulated emission and lasing. Semiconductor nanowires have recently been widely studied for use in integrated optoelectronic devices, such as…
The peculiar characteristics of random laser emission have been studied in many different media, leading to a classification of the working regimes based on the statistics of spectral fluctuations. Alongside such studies, the possibility to…
Calibrating displays is a basic and regular task that content creators must perform to maintain optimal visual experience, yet it remains a troublesome issue. Measuring display characteristics from different viewpoints often requires…
Speckle is a wave interference phenomenon that has been studied in various fields, including optics, hydrodynamics and acoustics. Speckle patterns contain spectral information of the interfering waves, and of the scattering medium that…
Stimulated Raman scattering is a well-known nonlinear process that can be harnessed to produce optical gain in a wide variety of media. This effect has been used to produce the first silicon-based lasers and high-gain amplifiers.…
Efficient generation of radiation in the mid- and far- infrared relies primarily on lasers and coherent nonlinear optical phenomena driven by lasers. This wavelength range lacks of luminescent devices because the spontaneous emission rate…
In this thesis, we explore random lasing from a system comprising of amplifying microresonators. Using Monte-Carlo simulation, we investigate the diffusive propagation of light in an amplifying medium with randomly suspended resonant…
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…
We report on studies of simultaneous continuous-wave mirrorless lasing on multiple optical transitions, realized by pumping hot cesium vapor with laser light resonant with the 6$S_{1/2}\rightarrow 8$P$_{3/2}$ transition. The multiplicity of…
Collective responses of localized surface plasmon resonances, known as surface lattice resonances (SLRs) in metal nanoparticle arrays, can lead to high quality factors (~100), large local-field enhancements and strong light-matter…
The random laser emission from the functionalized thienyl-S,S-dioxide quinquethiophene (T5OCx) in confined patterns with different shapes is demonstrated. Functional patterning of the light emitter organic material in well defined features…
We present a novel laser mode-locking scheme and discuss its unusual properties and feasibility using a theoretical model. A large set of single-frequency continuous-wave lasers oscillate by amplification in spatially separated gain media.…