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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…

Optics · Physics 2009-11-13 Z. H. Zhu , H. Liu , S. M. Wang , T. Li , J. X. Cao , W. M. Ye , X. D. Yuan , S. N. Zhu

We present a detailed numerical investigation of the tunability of a diffusive random laser when Mie resonances are excited. We solve a multimode diffusion model and calculate multiple light scattering in presence of optical gain which…

Optics · Physics 2015-06-23 Michele Gaio , Matilda Peruzzo , Riccardo Sapienza

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…

Optics · Physics 2011-11-24 Jonathan Andreasen , Patrick Sebbah , Christian Vanneste

We discuss the main features of a new optical system capable of laser action: the active complex optical network, or lasing network (LANER). The system is experimentally realized with optical fibers linked each other with suitable optical…

Optics · Physics 2019-02-27 Giovanni Giacomelli , Stefano Lepri , Cosimo Trono

We explore the ability of two-dimensional periodic atom arrays to produce light amplification and generate laser emission when gain is introduced through external optical pumping. Specifically, we predict that lasing can take place for…

Mesoscale and Nanoscale Physics · Physics 2018-10-24 Vahagn Mkhitaryan , Lijun Meng , Andrea Marini , F. Javier Garcia de Abajo

High-quality micro-lasers are key ingredients in non-linear optics, communication, sensing and low-threshold solar-pumped lasers. However, such micro-lasers exhibit negligible absorption of free-space broadband pump light. Recently, this…

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…

In standard lasers, light amplification requires population inversion between an upper and a lower state to break the reciprocity between absorption and stimulated emission. However, in a medium prepared in a specific superposition state,…

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…

Imaging is of great importance in everyday life and various fields of science and technology. Conventional imaging is achieved by bending light rays originating from an object with a lens. Such ray bending requires space-variant structures,…

Optics · Physics 2023-10-02 Wenzhe Liu , Jingguang Chen , Tongyu Li , Zhe Zhang , Fang Guan , Lei Shi , Jian Zi , C. T. Chan

We predict collective 'free-space' lasing in a dense nanoscopic emitter arrangement where dipole-dipole coupled atomic emitters synchronize their emission and exhibit lasing behavior without the need for an optical resonator. At the example…

Quantum Physics · Physics 2025-09-26 Anna Bychek , Raphael Holzinger , Helmut Ritsch

We report a proof-of-principle experiment where the refractive index of an atomic vapor is enhanced while maintaining vanishing absorption of the beam. The key idea is to drive alkali atoms in a vapor with appropriate control lasers and…

Quantum Physics · Physics 2009-01-09 N. A. Proite , B. E. Unks , J. T. Green , D. D. Yavuz

Electric susceptibility of a laser-dressed atomic medium is calculated for a model Lambda - like system including two lower states and a continuum structured by a presence of an autoionizing state or a continuum with a laser-induced…

Quantum Physics · Physics 2009-11-11 A. Raczynski , M. Rzepecka , J. Zaremba , S. Zielinska-Kaniasty

We address the problem of achieving a random laser with a cloud of cold atoms, in which gain and scattering are provided by the same atoms. In this system, the elastic scattering cross-section is related to the complex atomic…

Optics · Physics 2015-05-13 William Guerin , Nicolas Mercadier , Davide Brivio , Robin Kaiser

Random lasers are promising in the spectral regime, wherein conventional lasers are unavailable, with advantages of low fabrication costs and applicability of diverse gain materials. However, their practical application is hindered by high…

Optics · Physics 2022-12-19 ChulMin Oh , Ho Jin Ma , KyeoReh Lee , Do Kyung Kim , YongKeun Park

A transverse mode selective laser system with gain regulation by a digital micromirror device (DMD) is presented in this letter. The gain regulation in laser medium is adjusted by the switch of the patterns loaded on DMD. Structured pump…

Optics · Physics 2021-08-10 Zilong Zhang , Yuan Gao , Xin Wang , Suyi Zhao , Yuchen Jie , Changming Zhao

We report on a novel kind of transition in random lasers induced by the geometrical confinement of the emitting material. Different dye doped paper devices with controlled geometry are fabricated by soft-lithography and show two…

Optics · Physics 2015-06-22 N. Ghofraniha , I. Viola , A. Zacheo , V. Arima , G. Gigli , C. Conti

We demonstrate that a knowledge of the density-of-states and the eigenstates of a random system without gain, in conjunction with the frequency profile of the gain, can accurately predict the mode that will lase first. Its critical pumping…

Disordered Systems and Neural Networks · Physics 2009-11-07 Xunya Jiang , C. M. Soukoulis

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…

We demonstrate lasing mode selection in nearly circular semiconductor microdisks by shaping the spatial profile of optical pump. Despite of strong mode overlap, adaptive pumping suppresses all lasing modes except the targeted one. Due to…

Optics · Physics 2016-02-18 Seng Fatt Liew , Brandon Redding , Li Ge , Glenn S. Solomon , Hui Cao