English
Related papers

Related papers: Transient gain from $N_2^+$ in light filaments

200 papers

We report on experimental realization of impulsive rotational Raman scattering from neutral nitrogen molecules in a femtosecond laser filament using an intense self-induced white-light seeding "air laser" generated during the filamentation…

The diffuse reflectance (albedo) and transmittance of a Raman random gain medium are calculated via semi-analytic two-stream equations with power-dependent coefficients. The results show good agreement with the experimental data for barium…

Optics · Physics 2015-05-18 Adrian C. Selden

We report on the amplification of an optical vortex beam carrying orbital angular momentum via induced narrow Raman gain in an ensemble of cold cesium atoms. A 20\% single-pass Raman gain of a weak vortex signal field is observed with a…

Quantum Physics · Physics 2016-05-09 G. C. Borba , S. Barreiro , L. Pruvost , D. Felinto , J. W. R. Tabosa

Optical dual-pulse pumping actively creates quantum-mechanical superposition of the electronic and phononic states in a bulk solid. We here made transient reflectivity measurements in an n-GaAs using a pair of relative-phase-locked…

Mesoscale and Nanoscale Physics · Physics 2019-05-22 Kazutaka G. Nakamura , Kensuke Yokota , Yuki Okuda , Rintaro Kase , Takashi Kitashima , Yu Mishima , Yutaka Shikano , Yosuke Kayanuma

Raman spectroscopy uses light scattering to extract information on low-energy excitations of solids. The Raman process is described by diagrams which are fourth order in the light-matter interaction, and in particular the resonant…

Strongly Correlated Electrons · Physics 2024-01-30 Philipp Werner , Martin Eckstein , Naoto Tsuji

We demonstrate a direct measurement of the energy levels of impurity-trapped excitons in CaF$_2$:Yb$^{2+}$. The radically different radiative decay rates of the lowest exciton state and higher excited states enable the generation of a…

We investigate for the first time the enhancement of the stimulated Raman scattering in slow-light Silicon-on-Insulator (SOI) photonic crystal line defect waveguides. By applying the Bloch-Floquet formalism to the guided modes in a planar…

Optics · Physics 2010-04-12 J. F. McMillan , X. Yang , N. C. Panoiu , R. M. Osgood , C. W. Wong

Propagation of light in a highly scattering medium is among the most fascinating optical effect that everyone experiences on an everyday basis and possesses a number of fundamental problems which have yet to be solved. Conventional wisdom…

Photonics caught world attention since channel capacity limit of metallic interconnects approached due to research and design in high speed digital processors. Use of dielectrics, instead, suitable for light propagation was more attractive…

Optics · Physics 2024-12-04 Abdurrahman Javid Shaikh , Othman Sidek

Generation of laser-like narrow bandwidth emissions from nitrogen molecular ions generated in intense near- and mid-infrared femtosecond laser fields has aroused much interest because of the mysterious physics underlying such a phenomenon…

Optics · Physics 2018-02-28 Zhaoxiang Liu , Jinping Yao , Jinming Chen , Bo Xu , Wei Chu , Ya Cheng

Mechanism of transient population inversion in graphene with multi-splitted (interdigitated) top-gate and grounded back gate is suggested and examined for the mid-infrared (mid-IR) spectral region. Efficient stimulated emission after fast…

Mesoscale and Nanoscale Physics · Physics 2015-06-16 A. Satou , F. T. Vasko , T. Otsuji , V. V. Mitin

We theoretically propose a method to enhance Raman scattering by injecting a seeded light field which is correlated with the initially prepared atomic spin wave. Such a light-atom correlation leads to an interference in the Raman…

Quantum Physics · Physics 2013-05-29 Chun-Hua Yuan , L. Q. Chen , Z. Y. Ou , Weiping Zhang

Despite the tremendous progresses in wavefront control through or inside complex scattering media, several limitations prevent reaching practical feasibility for nonlinear imaging in biological tissues. While the optimization of nonlinear…

Optics · Physics 2016-12-06 Hilton B. de Aguiar , Sylvain Gigan , Sophie Brasselet

We report on the first observation of stimulated Raman scattering from a Lambda-type three-level atom, where the stimulation is realized by the vacuum field of a high-finesse optical cavity. The scheme produces one intracavity photon by…

Quantum Physics · Physics 2009-11-06 M. Hennrich , T. Legero , A. Kuhn , G. Rempe

We discuss the radiative transfer theory for translucent clouds illuminated by an extended background source. First we derive a rigorous solution based on the assumption that multiple scattering produce an isotropic flux. Then we derive a…

Solar and Stellar Astrophysics · Physics 2017-05-10 Davide Biganzoli , Marco Potenza , Massimo Robberto

We develop a generic theory for the resonant inelastic light (Raman) scattering by a conduction band quantum plasma taking into account the presence of the filled valence band in doped semiconductor nanostructures within a generalized…

Strongly Correlated Electrons · Physics 2009-11-07 Daw-Wei Wang , S. Das Sarma

Raman enhancement techniques are essential for fundamental studies in light-matter interactions and find widespread application in microelectronics, bio-chemical sensing, and clinical diagnosis. Two-dimensional (2D) materials and their van…

Mesoscale and Nanoscale Physics · Physics 2020-03-24 Medha Dandu , Kenji Watanabe , Takashi Taniguchi , Ajay K. Sood , Kausik Majumdar

We present a general model study of surface-enhanced resonant Raman scattering and fluorescence, focusing on the interplay between electromagnetic (EM) effects and the molecular dynamics as treated by a density matrix calculation. The model…

Other Condensed Matter · Physics 2007-05-23 Peter Johansson , Hongxing Xu , Mikael Käll , ;

We propose a scheme to realize the storage and retrieval of light pulses in a fast-light medium via a mechanism of active Raman gain (ARG). The system under consideration is a four-level atomic gas interacting with three (pump, signal and…

Optics · Physics 2017-11-15 Datang Xu , Zhengyang Bai , Guoxiang Huang

A near-infrared laser generates gain on transitions between the $\text{B}^{\text{2}} \Sigma_{\text{u}}^{\text{+}}$ and $\text{X}^{\text{2}} \Sigma_{\text{g}}^{\text{+}}$ states of the nitrogen molecular cation in part by coupling the…