Search results for "raman scattering"
showing 10 items of 284 documents
Four Wave Mixing in Photonic Crystal Fibers:<br /> Tuning Techniques
2016
We present an experimental and numerical study of four-wave mixing in photonic crystal fibers. Our objective is the development of tuning techniques based on tailoring de dispersion of the fibers. We demonstrate wide tuning ranges.
Chapter 3 Surface Plasmon Optics for the Characterization of Biofunctional Architectures
2007
Publisher Summary This chapter describes a wide variety of work employing surface plasmon resonance (SPR), surface plasmon field-enhanced fluorescence spectroscopy (SPFS), and surface plasmon field-enhanced diffraction spectroscopy (SPDS) analysis, specifically for investigations relevant to biofunctional, bio-affinity aspects. The SPR has shown already its impact on interfacial analysis. The combination of these three methods has the potential to generate more information and reveal details of biofunctional interfaces. The versatility of the SPR technique is shown by a vast amount of publications in the past decades; the method has matured into a well-accepted analytical tool for the chara…
Characterization of thin superconducting YBaCuO-films by Raman-spectroscopy
1988
We have investigated thin sputtered films of the high Tc material YBa2Cu3O7 by means of Raman spectroscopy at different stages of the preparation process. We find that the films are amorphous after sputtering. The Raman spectra indicate that random polycrystalline layers, as well as crystalline layers with preferred orientation, are obtained by an additional thermal treatment.
Raman measurements on GaN thin films for PV - purposes
2012
Raman scattering (RS) is a very important experimental tool to characterize the optical modes and another elementary excitations of materials. Among other issues it can determine for example the degree of crystalline quality and point defects like local modes. Therefore GaN - thin films and related compounds for photovoltaic purposes and as processed by several systems have been measured by this technique. The films were grown by Molecular Beam Epitaxy (MBE), Close Spaced Vapor Transport (CSVT) and Laser Ablation (LA) with the use of optimal growth parameters and substrates. Gallium nitride crystallizes in the wurtzite structure with 4 atoms in the unit cell and presents 7 allowed Raman mod…
Seeing a single molecule vibrate through time-resolved coherent anti-Stokes Raman scattering
2014
The vibrations of the chemical bonds of a single molecule are observed by employing time-resolved coherent anti-Stokes Raman scattering. A gold nanoantenna is used to enhance the signal from the molecule.
Plasmonic Biosensors for the Detection of Lung Cancer Biomarkers: A Review
2021
Lung cancer is the most common and deadliest cancer type globally. Its early diagnosis can guarantee a five-year survival rate. Unfortunately, application of the available diagnosis methods such as computed tomography, chest radiograph, magnetic resonance imaging (MRI), ultrasound, low-dose CT scan, bone scans, positron emission tomography (PET), and biopsy is hindered due to one or more problems, such as phenotypic properties of tumours that prevent early detection, invasiveness, expensiveness, and time consumption. Detection of lung cancer biomarkers using a biosensor is reported to solve the problems. Among biosensors, optical biosensors attract greater attention due to being ultra-sensi…
Perylene Derivatives As Useful SERRS Reporters, Including Multiplexing Analysis
2015
Five perylene bisimide (PBI) derivatives were designed and synthesized, on the basis of quantum-chemical calculations. The influence of halogen substituents on the shape and energy of the frontier orbitals and the Raman spectra were calculated, in the prospect use in surface-enhanced resonance Raman scattering (SERRS) studies. The corresponding experiments confirmed a very strong SERRS response in the presence of pristine (i.e., uncoated) gold nanoparticles. These spectra can be used for multiplexing measurements, namely measurements in which, by using a single laser excitation, one can recognize the simultaneous presence of several analytes.
Strong coupling between surface plasmon polaritons and β-carotene in nanolayered system.
2013
In this article we experimentally demonstrate the strong coupling between surface plasmon polaritons (SPP) and the S(2) state of β-carotene. The SPPs are excited by prism coupling technique on a thin silver film with β-carotene embedded in a polymer layer on top of that. Rabi splittings with energies 80 and 130 meV are observed in the recorded dispersion relations. Both coupled oscillator model and transfer matrix method are used to fit the experimental results. The scattered radiation of the propagating strongly coupled SPP-S(2) hybrids is collected and an increase of the low energy splitting to 120 meV is observed compared to the reflectivity data. In addition, we performed molecule excit…
Background-Free Second-Harmonic Generation Microscopy of Individual Carbon Nanotubes
2015
We use polarized second-harmonic generation (SHG) microscopy to investigate pristine air-suspended carbon nanotubes (CNT). We show that SHG originates from CNT chirality, allowing also different response for the two circular polarizations of fundamental light.
Surface plasmons and vibrations of self-assembled silver nanocolumns
2006
6 pags. ; 5 figs. 1 tab.