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Search Publications

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Displaying 3651 - 3675 of 74220

Near-Field Intensity Correlations in Semicontinuous Metal-Dielectric Films

October 12, 2021
Author(s)
K Seal, A K. Sarychev, H Noh, D A. Genov, A Yamilov, Vladimir Shalaev, Z C. Ying, H Cao
Spatial intensity correlation functions are obtained from near-field scanning optical microscope measurements of semicontinuous metal-dielectric films. The concentration of metal particles on a dielectric surface is varied over a wide range to control the

Near-Field Second Harmonic Microscopy of Thin Ferroelectric Films

October 12, 2021
Author(s)
V Smolyaninova, H Y. Liang, C H. Lee, C C. Davis, L D. Rotter, Debra Kaiser
Near-field second harmonic microscopy is ideally suited for studies of local nonlinearity and poling of ferroelectric materials at the microscopic level. Its main advantages in comparison with other scanning probe techniques are the possibility of fast

Near-Field, Spherical-Scanning Antenna Measurements With Nonideal Probe Locations

October 12, 2021
Author(s)
Ronald C. Wittmann, Bradley Alpert, Michael H. Francis
We introduce a near-field, spherical-scanning algorithm for antenna measurements that relaxes the usual condition requiring data points to be on a regular spherical grid. Computational complexity is of the same order as for the standard (ideal-positioning)

NEMI Group Recommends 'Standardized' Lead-Free Solder Alternative

October 12, 2021
Author(s)
J Bath, C A. Handwerker, E Bradley
Increasing global concern about the environment is bringing regulatory and consumer pressure on the electronics industry in Europe and Japan to reduce or completely eliminate the use of lead in products. As Europe and Japan move toward lead-free

NEMI Tin Whisker Test Method Standards

October 12, 2021
Author(s)
I Boguslavsky, P Bush, E Kam-Lum, M Kwoka, J McCullen, K Spalding, K Vo, Maureen E. Williams
The need to better understand whisker growth has dramatically increased as component suppliers convert from tin-lead (SnPb) finishes to Pb-free finishes of Sn and low -alloy-content Sn-based finishes. Whiskers are spontaneous growth of metal filaments

NEXAFS Characterization of Poly(amino acids)

October 12, 2021
Author(s)
N T. Samuel, Daniel A. Fischer, David G. Castner
The near-edge x-ray absorption fine structure (NEXAFS) spectra of poly(amino acids) at the carbon, nitrogen and oxygen k-edges are investigated in this study. The poly(amino acid) NEXAFS spectra at the k-edges closely resemble the spectra of the

NiO: A Charge Transfer or Mott-Hubbard Insulator

October 12, 2021
Author(s)
T M. Schuler, D L. Ederer, S Itza-Ortiz, G T. Woods, T A. Callcott, Joseph Woicik
Using site-specific soft x-ray emission and absoroption spectroscopy in conjunction with site-specific x-ray photoelectron spectroscopy, we measure the magnitude of the insulating band gap of NiO to be approximately 2.0 eV, comparable to that predicted by

Non-Contact Tuning Fork Position Sensing for Hollow-Pyramid Near-Field Cantilevered Probes

October 12, 2021
Author(s)
A Ambrosio, E Cafali, S Spadaro, S Patane, Maria Allegrini, D Albert, E Oesterschulze
We demonstrate that tuning fork sensing provides a stable non-contact mode operation when applied to near-field optical microscopy employing cantilevered probes. Detrimental damping effects that have so far limited the practical use of these otherwise very

On the Future of Scientific Publication

October 12, 2021
Author(s)
Peter Strickland, Andrew J. Allen
We give a brief review of the rapidly changing landscape for scientific publication, especially in regard to scientific archival journal publication. Some of the many challenges and opportunities are outlined. These include the various forms of open access

Optical Frequency Synthesis Based on Modelocked Lasers

October 12, 2021
Author(s)
S T. Cundiff, Jun Ye, John L. Hall
The synthesis of optical frequencies from the primary cesium microwave standard has traditionally been a difficult problem due to the large difference in frequencies. Recently a dramatic advance in this field has occurred due to the introduction of the use

Optical Probes for Monitoring Intercalation and Exfoliation in Melt Processed Polymer Nanocomposites

October 12, 2021
Author(s)
P H. Maupin, Jeffrey W. Gilman, Richard H. Harris Jr., S Bellayer, Anthony J. Bur, S C. Roth, A B. Morgan, J R. Harris, M Murariu
Laser induced fluorescence spectroscopy of the optical probe Nile Blue A in polymer clay nanocomposites is described. Concentration quenching of fluorescence dominates probe behavior until the clay platelets are physically separated by polymer

Optical Pulse Synthesis From Two Separate Femtosecond Lasers

October 12, 2021
Author(s)
R K. Shelton, L -. Ma, H C. Kapteyn, M M. Murnane, J L. Hall, Jun Ye
Two independent mode-locked femtosecond lasers are tightly synchronized and phase locked. The rms timing jitter between the lasers is 4.3 fs within a 160 Hz bandwidth. The rms noise of the beat frequency between the two optical combs is 140 mHz at 1s

Optimizing Available Tools for Obtaining Result Standardization: A Joint Committee on Traceability in Laboratory Medicine (JCTLM) Project

October 12, 2021
Author(s)
Mauro Panteghini, Federica Braga, Johanna Camara, Vincent Delatour, Katleen Van Uytfanghe, Hubert Vesper, Tianjiao Zhang
BACKGROUND: The JCTLM created a Task Force on Reference Measurement System Implementation (TFRMSI) to provide guidance on metrological traceability implementation for the in vitro diagnostics (IVD) community. CONTENT: TF-RMSI investigated the reference

Optimum Press and Sinter Processing for Aluminum/SiC Composites

October 12, 2021
Author(s)
G T. Campbell, R Raman, Richard J. Fields
Previous research by the present authors has revealed the importance of relative particle size [d(SiC)/d(Al)] in the development of strength in Al/SiC composites. The earlier work focused on just two size ratios. Here, the effect of numerous size ratios

Ordered Water Monolayer on Ultra-Smooth Hydroxylated Amorphous SiO^d2

October 12, 2021
Author(s)
I M. Aarts, A C. Pipino, J P. Hoefnagels, W M. Kessels, M C. van de Sanden
Polarized near-IR evanescent wave absorption spectra reveal the structure of awater monolayer bound to an ultra-smooth hydroxylated amorphous SiO2 surfaceunder equilibrium conditions. Employing a variant of cavity ring-downspectroscopy, combination spectra
Displaying 3651 - 3675 of 74220