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anti-Stokes Raman Scattering (anti-Stoke + raman_scattering)
Kinds of anti-Stokes Raman Scattering Selected AbstractsSignal generation and Raman-resonant imaging by non-degenerate four-wave mixing under tight focusing conditionsJOURNAL OF BIOPHOTONICS, Issue 3 2010Tyler Weeks Abstract The authors demonstrate Raman-resonant imaging based on the simultaneous generation of several nonlinear frequency mixing processes resulting from a 3-color coherent anti-Stokes Raman scattering (CARS) experiment. The interaction of three coincident short-pulsed laser beams simultaneously generates both 2-color (degenerate) CARS and 3-color (non-degenerate) CARS signals, which are collected and characterized spectroscopically , allowing for resonant, doubly-resonant, and non-resonant contrast mechanisms. Images obtained from both 2-color and 3-color CARS signals are compared and found to provide complementary information. The 3-color CARS microscopy scheme provides a versatile multiplexed modality for biological imaging, which may extend the capabilities of label-free non-linear microscopy, e.g. by probing multiple Raman resonances. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Two-beam multiplexed CARS based on a broadband oscillator,JOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2010Kentaro Furusawa Abstract A two-beam multiplexed coherent anti-Stokes Raman scattering (CARS) microscopy setup is demonstrated by using a broadband (BB) Ti:sapphire oscillator without using any specialty fibres. A well-defined spectral structure of the source leads to a delay-sensitive CARS measurement in two-colour CARS and also provides an efficient means of obtaining three-colour CARS signals combined with the dispersion compensation of the BB pulse. Our result implies that the background suppression is limited by the onset of the spurious signals caused by the different CARS process, qualitatively differing from what is typically observed in the CARS microscopy. Copyright © 2010 John Wiley & Sons, Ltd. [source] CARS thermometry revisited in lightof the intramolecular perturbation,JOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2010Michele Marrocco Abstract The rigid rotor approximation (RRA) is commonly assumed in the Raman cross section used in thermometric analysis based on coherent anti-Stokes Raman scattering (CARS). In this paper, we discuss instead the role of the coupling between molecular vibrations and rotations in view of the alterations found in the amplitude of CARS signals of basic molecules and, in the end, we demonstrate that the deviation of a few percent from the RRA results in corrections to the measured temperature that are comparable to the thermometric accuracy of very well-known Q-branch CARS measurements on nitrogen, which is unanimously regarded as the fundamental molecule in CARS thermometry. Copyright © 2010 John Wiley & Sons, Ltd. [source] New trends and recent advances in coherent Raman microscopy and nonlinear optical spectroscopy: introduction to the special issueJOURNAL OF RAMAN SPECTROSCOPY, Issue 7 2009A. Volkmer Abstract This special issue highlights 20 papers, presenting the latest theoretical and experimental developments and achievements in coherent anti-Stokes Raman scattering (CARS) microscopy and nonlinear optical spectroscopy. Most of them were presented at the seventh European Conference on Nonlinear Optical Spectroscopy (ECONOS 2008) jointly held with the first European Conference on CARS Microscopy (microCARS 2008) in Igls, Austria, May 25,27, 2008. Copyright © 2009 John Wiley & Sons, Ltd. [source] CARS microscopy of lipid stores in yeast: the impact of nutritional state and genetic backgroundJOURNAL OF RAMAN SPECTROSCOPY, Issue 7 2009Christian Brackmann Abstract We have developed a protocol for sub-micrometer resolved and chemically specific imaging of lipid storage in vivo employing coherent anti-Stokes Raman scattering (CARS) microscopy of one of the most important model organisms Saccharomyces cerevisiae,the yeast cell. By probing the carbon,hydrogen vibration using the nonlinear process of CARS, lipid droplets in the yeast cells clearly appear, as confirmed by comparative studies on relevant labeled organelles using two-photon fluorescence microscopy. From the images, unique quantitative data can be deduced with high three-dimensional resolution, such as the volume, shape, number, and intracellular location of the neutral lipid stores. We exemplify the strength and usability of the method for two cases: the impact on lipid storage of the nutritional condition (starvation and type of carbon source available) as well as of genetic modification of two fundamental metabolic regulation pathways involving carbohydrate and lipid storage (BCY1 and DGA1, LRO1, ARE1/2 deletions), respectively. While the impact of carbon source on the total cellular lipid volume was minimal, long-term starvation induces a significant accumulation of lipid droplets. We also confirm that the lipid-storage-deficient mutant is indeed unable to synthesize lipid droplets, and that the inability of the bcy1 -mutant to store carbohydrates is compensated by a two-fold increase in stored neutral lipids. We note that there is a significant cell-to-cell variability in neutral lipid storage in general, i.e. that there is a correspondence to the noise found for gene expression also in lipidomics. Copyright © 2009 John Wiley & Sons, Ltd. [source] Time-resolved coherent Raman and sum-frequency generation spectroscopy with wavelength-tunable, short-pulse, photonic-crystal fiber light sourcesJOURNAL OF RAMAN SPECTROSCOPY, Issue 8 2007A. M. Zheltikov Abstract Photonic-crystal fibers deliver frequency-tunable radiation within the wavelength range stretching from the ultraviolet to the near-infrared with output pulse widths from tens of femtoseconds to a few picoseconds and peak powers from a few watts to several megawatts, suggesting a convenient, efficient, and compact fiber format of short-pulse sources for time-resolved nonlinear spectroscopy and microscopy. Here, we examine the potential of photonic-crystal fiber light sources for time-resolved studies of ultrafast population and coherence relaxation dynamics in molecular systems using coherent anti-Stokes Raman scattering and two-photon-resonant sum-frequency generation. Copyright © 2007 John Wiley & Sons, Ltd. [source] Polarization coherent anti-stokes Raman scattering using noisy lightJOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2007Lindsay R. Weisel Abstract Several polarization studies on the noisy light version of coherent anti-Stokes Raman scattering (CARS) exist in the literature. However, the full advantages of polarization CARS (P-CARS), which are so useful in conventional and short-pulse CARS methods, have not yet been exploited in the noisy light version. This work presents experimental realization of fully functional P-CARS using noisy light. Several examples demonstrate the advantages brought by P-CARS. This includes the ,classic' example of benzene in carbon tetrachloride. Also presented are the carbon,carbon double bond stretches in acrylonitrile and 1-hexene. An interesting, and not fully understood, detection polarization angle dependence is discussed. Applications to an m -xylene/benzene mixture and an alkaline solution of the amino acid phenylalanine are presented. Copyright © 2006 John Wiley & Sons, Ltd. [source] Frequency shifting and pulse shaping with photonic-crystal fibers for coherent nonlinear spectroscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 6 2006Ya. M. Linik Abstract The frequency-shifted and pulse-shaped output of photonic-crystal fibers (PCFs) pumped by amplified femtosecond Cr:forsterite laser pulses is employed for frequency- and time-resolved four-wave mixing (FWM) spectroscopy. Cross-correlation frequency-resolved optically gated laser-induced grating (LIG) technique is applied for the characterization of the pulse-shaped blue-shifted PCF output. The light pulses produced in the PCF are combined with the second-harmonic output of the Cr:forsterite laser, to probe a doublet of Raman resonances in the nonlinear response of a test object by means of coherent anti-Stokes Raman scattering (CARS). Copyright © 2006 John Wiley & Sons, Ltd. [source] Temperature measurements in combustion,not only with CARS: a look back at one aspect of the European CARS WorkshopJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2003W. Stricker Abstract Temperature is perhaps the most important quantity in combustion research and technology. The potential and state of the art of various laser-based diagnostics used for the determination of temperature in laboratory flames and practical combustion devices are discussed and illustrated with a few representative examples from our laboratory. The emphasis is on coherent anti-Stokes Raman scattering (CARS), the main topic of the European CARS Workshop in the past. As a result, CARS is today the most matured and proven technique for technical applications. In addition to CARS, however, linear laser spectroscopic methods also deliver valuable and supplementary information on temperature in combustion. Copyright © 2003 John Wiley & Sons, Ltd. [source] J-aggregation visualized with two-photon-resonant third-harmonic generationJOURNAL OF RAMAN SPECTROSCOPY, Issue 12 2003D. A. Akimov Abstract Third-harmonic generation (THG) with a two-photon-absorption (TPA) type resonance was used to monitor the J-aggregation of ethyl thiacarbocyanine in aqueous solution. Correlations between TPA-resonant THG and two-photon-excited photoluminescence are revealed, indicating the significance of excited states for non-linear-optical processes in J-aggregating solutions. Similar to Raman resonances in coherent anti-Stokes Raman scattering, TPA resonances in THG allow THG enhancement to be effectively decoupled from the growth of radiation losses. Copyright © 2003 John Wiley & Sons, Ltd. [source] Detection of single lipid bilayers with coherent anti-Stokes Raman scattering (CARS) microscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2003Eric O. Potma Abstract We investigated vibrational imaging of phospholipid bilayers with CARS microscopy. Single lipid membranes of supported bilayers, giant unilamellar vesicles and intact erythrocyte membrane are detected with the strong resonant signal of the C,H stretching vibration. In addition, it is shown that the CARS signal field of the lipids near the glass/water interface is amplified through mixing with the back-reflected non-resonant CARS field of the glass coverslip. Furthermore, interference effects between two separate bilayers are observed, allowing intermembrane distances to be determined beyond the diffraction-limited resolution of the microscope. Copyright © 2003 John Wiley & Sons, Ltd. [source] Nano-optical dimension of coherent anti-Stokes Raman scatteringLASER PHYSICS LETTERS, Issue 9 2004A. M. Zheltikov Abstract The potential of coherent anti-Stokes Raman scattering (CARS) as a local probe for nanocomposite materials is theoretically analyzed. In view of the interference nature of CARS spectra and the high spatial resolution, CARS is argued to be ideally suited for the metrology of nanostructures and nanocomposite materials, as well as for the sensing of Raman-active species in a nanocomposite host, allowing a nano-scale extension of CARS methodology, referred to as nanoCARS. Local-fieldenhancement of CARS in nanostructures allows the creation of efficient nanoCARS sensors. (© 2004 by ASTRO, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Intracellular Imaging of HCV RNA and Cellular Lipids by Using Simultaneous Two-Photon Fluorescence and Coherent Anti-Stokes Raman Scattering MicroscopiesCHEMBIOCHEM, Issue 12 2006Xiaolin Nan Hepatitis C virus (HCV) infection is associated with changes in host-cell lipid metabolism. Here we describe a new approach for detecting HCV RNA using two-photon fluorescence (TPF), and HCV-associated changes in cellular lipids using coherent anti-Stokes Raman scattering (CARS) microscopy. By combining the two types of microscopy with a common laser source, we visualized both phenomena simultaneously and profiled cellular lipids and subcellular localization of RNA in real time. [source] Triple-Resonance Coherent Anti-Stokes Raman Scattering MicrospectroscopyCHEMPHYSCHEM, Issue 2 2009Wei Min Dr. Abstract Fluorescence-free microscopy: A new nonlinear optical microspectroscopy technique, femtosecond (fs) triple-resonance coherent anti-Stokes Raman scattering, in which the amplitude and phase of input fs laser pulses are optimally shaped to be in triple resonance with the molecular electronic and vibrational transitions, generates a coherent nonlinear signal beam at a new color with a highest possible efficiency (see figure). [source] | ||||||||||