Related papers: High gain backward lasing in air
The increasing availability of high-power Yb-based ultrafast laser-amplifier systems has opened the possibility of air filamentation at high repetition rates >1 kHz. In this new regime, accumulation effects cannot be ruled out, therefore,…
Steady-state plasmonic lasing is studied theoretically for a system consisting of many dye molecules arranged regularly around a gold nano-sphere. A three-level model with realistic molecular dissipation is employed to analyze the…
We report on the lasing in air and pure nitrogen gas pumped by a single 800 nm femtosecond laser pulse. Depending on gas pressure, incident laser power and beam convergence, different lasing lines are observed in the forward direction with…
Air lasing provides a promising technique to remotely produce coherent radiation in the atmosphere and attracts continuous attention. However, the polarization properties of N2+ lasing with seeding has not been understood since it was…
We make an adaptation of laser modelling equations to describe the behavior of a phonon laser (saser). Our saser consists of an AlGaAs/GaAs double barrier heterostructure designed to generate an intense beam of transversal acoustic (TA)…
We propose and analyze theoretically a double magnetic plasmon resonance nanolaser, in which Ytterbium-erbium co-doped material is used as the gain medium. Through design of the double magnetic resonance modes, pumping light (980nm) can be…
A diamond-like carbon circular target is proposed to improve the $\gamma$-ray emission and pair production with lasers intensity of $8\times 10^{22} ~\mathrm{W/cm^2}$ by using two-dimensional particle-in-cell simulations with quantum…
Collection of weak signals from remote locations is the primary goal and the primary hurdle of optical stand-off detection schemes. Typically, the measured signal is enhanced using large numerical aperture collection optics and high gain…
The wealth of work in backward Raman amplification in plasma has focused on the extreme intensity limit, however backward Raman amplification may also provide an effective and practical mechanism for generating intense, broad bandwidth,…
We realize a laser with a cloud of cold rubidium atoms as gain medium, placed in a low-finesse cavity. Three different regimes of laser emission are observed corresponding respectively to Mollow, Raman and Four Wave Mixing mechanisms. We…
The phonon analog of an optical laser has long been a subject of interest. We demonstrate a compound microcavity system, coupled to a radio-frequency mechanical mode, that operates in close analogy to a two-level laser system. An inversion…
Hybrid pumping appears as a promising compromise in order to reach the much coveted goal of an electrically pumped organic laser. In such configuration the organic material is optically pumped by an electrically pumped inorganic device on…
Stimulated emission in small-molecule organic films at a high dye concentration is generally hindered by fluorescence quenching, especially in the red region of the spectrum. Here we demonstrate the achievement of high net gains (up to 50…
A laser can be understood as thermodynamic engine converting heat to a coherent single mode field close to Carnot efficiency. From this perspective spectral shaping of the excitation light generates a higher effective temperature on the…
Atoms can scatter light and they can also amplify it by stimulated emission. From this simple starting point, we examine the possibility of realizing a random laser in a cloud of laser-cooled atoms. The answer is not obvious as both…
Reabsorption, the multiple scattering of spontaneously emitted photons in optically thick gases, is a major limitation to efficient optical pumping and laser cooling in ultracold gases. We report mitigation of reabsorption using spatial and…
The electric field in laser-driven plasma wakefield acceleration is orders of magnitude higher than conventional radio-frequency cavities, but the energy gain is limited by dephasing between the ultra-relativistic electron bunch and the…
Usually, photons are described by plane waves with a definite 4-momentum. In addition to plane-wave photons, "twisted photons" have recently entered the field of modern laser optics; these are coherent superpositions of plane waves with a…
Laser beams carrying orbital angular momentum (OAM) provide an additional degree of freedom and have found wide applications ranging from optical communications and optical manipulation to quantum information. The efficient generation and…
A method is proposed for producing monoergetic, high-quality ion beams in vacuum, via direct acceleration by the electromagnetic field of two counterpropagating, variable-frequency lasers: ions are trapped and accelerated by a beat-wave…