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Using a density matrix approach, we study the simplest systems that display both gain and feedback: clusters of 2 to 5 atoms, one of which is pumped. The other atoms supply feedback through multiple scattering of light. We show that, if the…

Quantum Physics · Physics 2015-06-26 Tom Savels , Allard P. Mosk , Ad Lagendijk

We have fabricated a layered nano-composite by alternating metal and gain medium layers, the gain dielectric consisting of a polymer incorporating optically pumped dye molecules. Exploiting an improved version of the effective medium…

Optics · Physics 2015-05-28 Carlo Rizza , Andrea Di Falco , Alessandro Ciattoni

We present a novel approach to enhance THz nonlinearity by the resonant excitation of two-dimensional plasmons in grating-gate plasmonic crystals. Using a high-electric-field THz pump-THz probe technique, we investigate the nonlinear…

We report a detailed study of the strong near-field Raman scattering enhancement which takes place in tip-enhanced Raman scattering (TERS) in indium nitride. In addition to the well-known first-order optical phonons of indium nitride,…

Stimulated Raman spectroscopy has become a powerful tool to study the spatiodynamics of molecular bonds with high sensitivity, resolution and speed. However, sensitivity and speed of state-of-the-art stimulated Raman spectroscopy are…

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…

Microscopic pyramidal pits in a reflective surface, a geometry similar to a retroreflector, are frequently used to enhance signal strength. The enhancement effect is generally attributed to surface plasmons, however, the sub-wavelength to…

Optics · Physics 2009-12-18 M. Mechler , S. V. Kukhlevsky , A. Mechler , D. McNaughton

We investigate theoretically the formation of two-component light with superluminal group velocity in a medium controlled by four Raman pump fields. In such an optical scheme only a particular combination of the probe fields is coupled to…

Quantum Physics · Physics 2016-08-10 V. Kudriašov , J. Ruseckas , A. Mekys , A. Ekers , N. Bezuglov , G. Juzeliūnas

High-quality microresonators can greatly enhance light-matter interactions and are excellent platforms for studying nonlinear optics. Wavelength conversion through nonlinear processes is the key to many applications of integrated optics.…

Optics · Physics 2024-06-27 Yuxuan He , Xiongshuo Yan , Jiangwei Wu , Xiangmin Liu , Yuping Chen , Xianfeng Chen

We study Raman scattering in active media placed in proximity of different types of metal nanostructures, at wavelengths that display either Fabry-Perot or plasmonic resonances, or a combination of both. We use a semi-classical approach to…

Optics · Physics 2015-06-05 M. Scalora , M. A. Vincenti , D. de Ceglia , M. Grande , J. W. Haus

Broadband energy-time entanglement can be used to enhance the rate of two-photon absorption (TPA) by combining a precise two-photon resonance with a very short coincidence time. Because of this short coincidence time, broadband TPA is not…

Quantum Physics · Physics 2023-12-04 Baihong Li , Holger F. Hofmann

We study transmission stabilization against radiation emission in soliton-based nonlinear optical waveguides with weak linear gain-loss, cubic loss, and delayed Raman response. We show by numerical simulations with perturbed nonlinear…

Optics · Physics 2018-08-08 Avner Peleg , Debananda Chakraborty

We demonstrate the acquisition of stimulated Raman scattering spectra with the use of a single femtosecond pulse. High resolution vibrational spectra are obtained by shifting the phase of a narrow band of frequencies in the broadband input…

Optics · Physics 2015-05-20 Hadas Frostig , Ori Katz , Adi Natan , Yaron Silberberg

We demonstrate theoretically and confirm experimentally a new mechanism of resonant electromagnetic transparency, which yields extremely narrow isolated symmetric Lorentzian lines of full transmission in metamaterials. It exploits the long…

Optics · Physics 2013-10-21 V. A. Fedotov , A. V. Rogacheva , V. Savinov , D. P. Tsai , N. I. Zheludev

The use of simple, fast and economic experimental tools to characterize low-dimensional materials is an important step in the process of democratizing the use of such materials in laboratories around the world. Raman spectroscopy has arisen…

We show theoretically that stimulated spin flip Raman scattering can be used to inject spin currents in doped semiconductors with spin split bands. A pure spin current, where oppositely oriented spins move in opposite directions, can be…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Ali Najmaie , E. Ya. Sherman , J. E. Sipe

We measure the resonant forward scattering of light by a highly saturated atomic medium through the flashes emitted immediately after an abrupt extinction of the probe beam. The experiment is done in a dilute regime where the phenomena are…

Atomic Physics · Physics 2021-01-05 C. C. Kwong , T. Wellens , K. Pandey , D. Wilkowski

Frequency combs have revolutionized optical frequency metrology, allowing one to determine highly accurate transition frequencies of a wealth of molecular species. Despite a recognized scientific interest, these progresses have only…

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…

Monolayers of ReS2 were grown by a chemical vapor deposition technique on SiO2/Si substrates and investigated at room temperature by using micro-Raman, micro-photoluminescence (PL) and absorbance spectroscopies. The Raman scattering…

Materials Science · Physics 2024-04-23 Solomon Ojo , Juwon Onasanya , Morad Benamara , Bothina Hamad , M. O. Manasreh