We report experimental data that indicate an anti-Stokes Raman emission, reminiscent of coherent antiStokes raman scattering. It originates from a wave mixing process between the incident laser light l and Stokes Raman light s generated by a surface enhanced Raman scattering SERS mechanism. The variation of anti-Stokes SERS spectra of single-walled carbon nanotubes, copper phthalocyanine, and p...

Shifted Excitation Raman Difference Spectroscopy (SERDS) implemented with two wavelength-stabilized laser diodes with fixed wavelength separation is discussed as an effective method for dealing with the effects of fluorescence in Raman spectroscopic analysis. In this presentation we discuss the results of both qualitative and quantitative SERDS analysis of a variety of strongly fluorescing samp...

In 1976 Byer proposed using stimulated rotational Raman scattering in hydrogen gas as an efficient method of frequency conversion in the infrared.' In particular, it was noted that stimulated Raman scattering in para-H 2 gas with a CO2 laser pump generates 16-gm radiation, which is of potential use for UF 6 isotope enrichment. It was subsequently learned that others have also suggested stimulat...

We report the observation of a strong 2D band Raman in twisted bilayer graphene (tBLG) with large rotation angles under 638 nm and 532 nm visible laser excitations. The 2D band Raman intensity increased four-fold as opposed to the two-fold increase observed in single-layer graphene. The same tBLG samples also exhibited rotation-dependent G-line resonances and folded phonons under 364 nm UV lase...

We propose and develop a new way for nonscanning coherent anti-Stokes Raman scattering (CARS) imaging by using CARS holography, which can capture, at a single shot, both the amplitude and the phase of a coherent Raman image. It hence allows for chemically selective three-dimensional imaging at a laser pulse duration limited speed, which is not possible to achieve by using any of the existing la...

Raman spectra of zinc phthalocyanine monolayers, adsorbed on gold and on glassy carbon surfaces (electrodes), are presented. These spectra have been recorded with the electrodes inside and outside an electrochemical cell filled with an aqueous electrolyte. A confocal Raman microspectrometer was used. It was demonstrated that, because this spectrometer uses low laser intensities, no damage of th...

We present results on a Raman laser-system that resonantly drives a closed two-photon transition between two levels in different hyperfine ground states of (87)Rb. The coupler is based on a novel optical design for producing two phase-coherent optical beams to drive a Raman transition. Operated as an outcoupler, it produces an atom laser in a single internal atomic state, with the lower diverge...

We demonstrate how the frequency of a single-mode cw dye laser can be translated by 1.772 GHz using stimulated Raman scattering in sodium vapor. The output of a sodium Raman laser, the frequency-translated beam, is shown to be highly correlated in frequency with the dye-laser pump beam. The bandwidth of the 1.772-GHz heterodyne beat signal between the two beams is found to be as narrow as 440 H...