Quantitative Analysis of Raman Spectra in Si/SiGe Nanostructures

2013 ◽  
Vol 1510 ◽  
Author(s):  
Selina Mala ◽  
Leonid Tsybeskov ◽  
Jean-Marc Baribeau ◽  
Xiaohua Wu ◽  
David J. Lockwood
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
Quantitative Analysis ◽  
Raman Spectra ◽  
Instrumental Response ◽  
Sample Surface ◽  
Stray Light ◽  
Raman Signal ◽  
Longitudinal Acoustic ◽  
Local Sample

ABSTRACTWe present comprehensive quantitative analysis of Raman spectra in two-(Si/SiGe superlattices) and three-(Si/SiGe cluster multilayers) dimensional nanostructures. We find that the Raman spectra baseline is due to the sample surface imperfection and instrumental response associated with the stray light. The Raman signal intensity is analyzed, and Ge composition is calculated and compared with the experimental data. The local sample temperature and thermal conductivity are calculated, and the spectrum of longitudinal acoustic phonons is explained.

Mechanical and thermal properties of polymer micro- and nanocomposites

2011 ◽  
Vol 31 (2-3) ◽  
Author(s):  
Stephan J. Picken ◽  
Alexander V. Korobko ◽  
Eduardo Mendes ◽  
Ben Norder ◽  
Veronika V. Makarova ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
Thermal Properties ◽  
Quantitative Analysis ◽  
Composite Materials ◽  
Shape Factor ◽  
Tensile Modulus ◽  
Particle Aggregation ◽  
Mechanical And Thermal Properties ◽  
Single Model

Abstract We have analyzed the thermal conductivity and the tensile modulus of composite materials within the framework of the Halpin-Tsai and Lewis-Nielsen models. The parameter linking thermal conductivity and tensile modulus together is the shape factor of the (nano)filler. Model analysis based on experimental data shows that particle aggregation into a weak mechanical network may be required to achieve good correlation between thermal conductivity and the Young’s modulus when analyzing the data within the framework of a single model and requiring the same value of the shape factor. We believe this approach will make quantitative analysis of nanocomposite thermal properties possible.

Models and Methods for Quantitative Analysis of Surface-Enhanced Raman Spectra

2014 ◽  
Vol 18 (2) ◽  
pp. 525-536 ◽  
Author(s):  
Shuo Li ◽  
James O. Nyagilo ◽  
Digant P. Dave ◽  
Jean Gao
Keyword(s):  
Quantitative Analysis ◽  
Raman Spectra ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

scholarly journals Raman Spectra of Nanodiamonds: New Treatment Procedure Directed for Improved Raman Signal Marker Detection

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Raoul R. Nigmatullin ◽  
Dumitru Baleanu ◽  
Diana Povarova ◽  
Numan Salah ◽  
Sami S. Habib ◽  
...  
Keyword(s):  
Raman Spectra ◽  
High Refractive Index ◽  
Spectroscopic Studies ◽  
Raman Signal ◽  
Heating Rates ◽  
Inert Core ◽  
Optimal Linear ◽  
Linear Smoothing ◽  
New Treatment ◽  
Increasing Temperature

Detonation nanodiamonds (NDs) have shown to be promising agents in several industries, ranging from electronic to biomedical applications. These NDs are characterized by small particle size ranging from 3 to 6 nm, while having a reactive surface and a stable inert core. Nanodiamonds can exhibit novel intrinsic properties such as fluorescence, high refractive index, and unique Raman signal making them very attractive imaging agents. In this work, we used several nanodiamond preparations for Raman spectroscopic studies. We exposed these nanodiamonds to increasing temperature treatments at constant heating rates (425–575°C) aiding graphite release. We wanted to correlate changes in the nanodiamond surface and properties with Raman signal which could be used as adetection marker. These observations would hold potential utility in biomedical imaging applications. First, the procedure of optimal linear smoothing was applied successfully to eliminate the high-frequency fluctuations and to extract the smoothed Raman spectra. After that we applied the secondary Fourier transform as the fitting function based on some significant set of frequencies. The remnant noise was described in terms of the beta-distribution function. We expect this data treatment to provide better results in biomolecule tracking using nanodiamond base Raman labeling.

HPHT synthesis and enhanced TE performance of Te and Sn/Se elements binary-doped CoSb3

2019 ◽  
Vol 12 (01) ◽  
pp. 1850105 ◽  
Author(s):  
Hairui Sun ◽  
Pin Lv ◽  
Chao Wang ◽  
Yunxian Liu ◽  
Xiaopeng Jia ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thermal Conductivity ◽  
High Pressure ◽  
High Temperature ◽  
Seebeck Coefficient ◽  
Grain Boundaries ◽  
Preparation Methods ◽  
Synthesis Time ◽  
Lattice Disorder ◽  
Positive Effect

A series of binary-doped CoSb3 with Te and Se/Sn bulk compounds Co4Sb[Formula: see text]TexSny/Sey ([Formula: see text] and 0.6, [Formula: see text] and 0.3), have been successfully prepared via a simple high pressure and high-temperature (HPHT) method. And, the influence of the doping elements on the microstructure of the samples synthesized under diverse pressures and the corresponding TE performance were studied in detail. Comparing with other preparation methods, the synthesis time of HPHT was acutely shortened. The obtained samples contain more grain boundaries, lattice disorder, dislocations and the possible “nanodot”, which have positive effect on reducing thermal conductivity. The experimental data indicate that the absolute values of Seebeck coefficient increases with pressure. What’s more, the thermal conductivities show a monotone decreasing trend as the synthesis pressure rises. The minimum value obtained is 1.93[Formula: see text]Wm[Formula: see text]K[Formula: see text] at normal temperature for Co4Sb[Formula: see text]Te[Formula: see text]Se[Formula: see text] prepared under 3[Formula: see text]GPa.

Raman investigations of collective vibrational motions in van der Waals liquids

1985 ◽  
Vol 63 (7) ◽  
pp. 2047-2053 ◽  
Author(s):  
S. Bratos ◽  
G. Tarjus
Keyword(s):  
Experimental Data ◽  
Raman Spectra ◽  
Van Der Waals ◽  
Zero Order ◽  
Partially Coherent ◽  
Present Context

Recent investigations of collective vibrational motions in pure van der Waals liquids and in their isotopic mixtures are reviewed. Experimental data are enumerated first. The theory is presented later, separately, for non-composite and composite bands of both isotropic and anisotropic Raman spectra. It is shown that isotropic Raman processes are partially coherent and contain information about collective vibrational motions in liquids. In turn, anisotropic Raman processes are incoherent in the zero-order description and their study is less important in the present context.

Symmetry Coordinates and Tentative Force Field Analysis of a PMo12O40 Model with the Keggin Structure

1976 ◽  
Vol 31 (12) ◽  
pp. 1589-1600 ◽  
Author(s):  
Lennart Lyhamn ◽  
S. J. Cyvin ◽  
B. N. Cyvin ◽  
J. Brunvoll
Keyword(s):  
Experimental Data ◽  
Force Field ◽  
Force Constant ◽  
Raman Spectra ◽  
Vibrational Analysis ◽  
Field Analysis ◽  
Infrared And Raman Spectra ◽  
Symmetry Coordinates ◽  
Force Field Analysis ◽  
Complex Ion

Abstract A complete vibrational analysis is performed for the 53 atomic PMo12O40 model of Td symmetry. The symmetry coordinates are classified into those of (a) ligand vibrations, (b) framework-ligand couplings, (c) framework vibrations, and (d) interligand vibrations. Simple valence force fields are estimated, and the influence of inclusion of redundancies on the calculated frequencies and symmetry force constants is investigated. Comments are made on calculated symmetry force constant values up to 345 mdyne/Å. Vibrational frequencies are calculated for the Mo3O7 and Mo3O13 units and for the PMo12O403- complex ion. For the latter compound the calculated values are compared with experimental data from infrared and Raman spectra.

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