NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications

NIST Authors in Bold

Displaying 801 - 825 of 910

Neutron-Diffraction Measurements of Magnetic Order and a Structural Transition in the Parent BaFe2As2 Compound of FeAs-Based High-Temperature Superconductors

December 17, 2008
Author(s)
Qingzhen Huang, Yiming Qiu, Wei Bao, Mark Green, Jeffrey Lynn, Y. C. Gasparovic, T. Wu, G. Wu, X. H. Chen
The recent discovery of superconductivity in (Ba,K)Fe2As2, which crystallizes in the ThCr2Si2 (122) structure as compared with the LnFeAsO (Ln is lanthanide) systems that possess the ZrCuSiAs (1111) structure, demonstrates the exciting potential of the

Neutron Transmission of Single-Crystal Magnesium Fluoride

November 27, 2008
Author(s)
John Barker, David F. Mildner, Jose Rodriguez Rivera, P. Thiyagarajan
The neutron attenuation through single-crystal magnesium fluoride has been measured as a function of wavelength at both room temperature and 77 K. These data confirm a total cross section that is lower than MgO for wavelengths greater than 0.2 nm. MgF 2

Pressure-induced volume-collapsed tetragonal phase of CaFe 2 As 2 as seen via neutron scattering

November 24, 2008
Author(s)
A. Kreyssig, Mark Green, Y. Lee, G. D. Samolyuk, Pawel Zajdel, Jeffrey Lynn, S. L. Bud'ko, M. S. Torikachvili, N. Ni, S. Nandi, Juscelino Leao, Sarah Poulton, D. N. Argyriou, B. N. Harmon, R. J. McQueeny, P. C. Canfield, A. I. Goldman
Recent investigations of the superconducting iron-arsenide families have highlighted the role of pressure, be it chemical or mechanical, in fostering superconductivity. Here we report that CaFe2As2 undergoes a pressure-induced transition to a nonmagnetic

Unusual Heavy-mass Nearly Ferromagnetic State with a Surprisingly Large Wilson Ratio in Double Layered Ruthenates (Sr 1-x Ca x ) 3 Ru 2 O 7

November 14, 2008
Author(s)
Z Qu, L Spinu, H Q. Yuan, V Dobrosavljevic, Wei Bao, Jeffrey Lynn, M Nicklas, J Peng, T J. Liu, F Fobes, E Flesch, Z Q. Mao
We report a very unusual heavy-mass nearly ferromagnetic state with a surprisingly large Wilson ratio Rw (e.g., Rw 700 for x = 0.2) in double layered ruthenates (Sr 1- xCa x) 3Ru 2O 7. This state does not evolve into a long-range ferromagnetic order

Phase and Valence Transitions in Ba^2^LnSn x Nb 1-x O 6-d

November 1, 2008
Author(s)
Paul J. Saines, Brendan J. Kennedy, Bernt Johannessen, Sarah Poulton
The structures of compounds in the perovskite series Ba2LnSnxNb1−xO6−δ (Ln=Pr and Tb and x=0, 0.1, 0.2, ..., 1.0) have been examined using synchrotron X-ray and neutron diffraction. It was found that niobate members of both series feature full B-site

Structural and magnetic phase diagram of CeFeAsO1- xFx and its relation to high-temperature superconductivity

October 26, 2008
Author(s)
Jun Zhao, Qingzhen Huang, Clarnia dela Cruz, Shiliang Li, Jeffrey Lynn, Ying Chen, Mark Green, G. F. Chen, Z. C. Li, J. L. Luo, N. L. Wang, Pengcheng Dai
Recently, high-transition-temperature (high-Tc) superconductivity was discovered in the iron pnictide RFeAsO1−xFx (R, rare-earth metal) family of materials. We use neutron scattering to study the structural and magnetic phase transitions in CeFeAsO1−xFx as

Collective dynamics in the Heisenberg pyrochlore antiferromagnet Gd 2 Sn 2 O 7

October 22, 2008
Author(s)
J. R. Stewart, Jason Gardner, Yiming Qiu, G. Ehlers
Gd2Sn2O7 is believed to be a good approximation to a Heisenberg antiferromagnet on a pyrochlore lattice with exchange and dipole-dipole interactions. The system is known to enter a long-range ordered ground state (the "Palmer Chalker" state) below Tc = 1 K

Neutron Scattering Study of the Excitation Spectrum of Solid Helium At Ultra-low Temperatures

October 1, 2008
Author(s)
Elizabeth Blackburn, John Goodkind, Sunil K. Sinha, Collin Broholm, John R. Copley, Ross W. Erwin
There has been a resurgence of interest in the properties of Solid Helium due to the recent discovery of non-classical rotational inertia (NCRI) in solid 4He by Chan and coworkers below 200 mK which they have interpreted as a transition to a "supersolid"

The Nature of Deuterium Arrangements in YD3 and other Rare-Earth Trideuterides

September 30, 2008
Author(s)
Terrence J. Udovic, Qingzhen Huang, Antonio Santoro, John J. Rush
The efficacy of different structural models for describing the observed neutron-powder-diffraction (NPD) measurements of bulk polycrystalline YD3 as well as other hexagonal rare-earth (i.e., Nd, Tb, Dy, Ho, Er, and Tm) trideuteride powders has been

External Magnetic Field Effects on a Distorted Kagome Antiferromagnet

September 2, 2008
Author(s)
J.-H. Kim, Sungdae Ji, S.-H. Lee, B. Lake, Taner N. Yildirim, H. Nojiri, H. Kikuchi, K. Habicht, Yiming Qiu, K. Kiefer
We report bulk magnetization, and elastic and inelastic neutron scattering measurements under an external magnetic field, H, on the weakly coupled distorted kagom¿e system, Cu 2(OD) 3Cl. Our results show that the ordered state below 6.7 K is a canted

Signature of magnetic phase separation in the ground state of Pr 1 - x Ca x MnO 3

August 27, 2008
Author(s)
Hao Sha, F Ye, Pengcheng Dai, J. A. Fernandez-Baca, D Mesa, Jeffrey Lynn, Y Tomioka, Y Tokura, Jiandi Zhang
Neutron scattering has been used to investigate the evolution of long- and short-range charge-ordered (CO), ferromagnetic, and antiferromagnetic (AF) correlations in single crystals of Pr1−xCaxMnO3. The existence and population of spin clusters as

Neutron-scattering study of the oxypnictide superconductor LaFeAsO 0.87 F 0.13

August 26, 2008
Author(s)
Yiming Qiu, M. Kofu, Wei Bao, S.-H. Lee, Qingzhen Huang, Taner N. Yildirim, John R. Copley, Jeffrey Lynn, T. Wu, G. Wu, X. H. Chen
The recently discovered superconductor LaO0.87F0.13FeAs (TC≈26 K) was investigated using the neutron-scattering technique. No spin-density-wave (SDW) order was observed in the normal state or in the superconducting state, both with and without an applied

Magnetic order of the iron spins in NdFeAsO

August 21, 2008
Author(s)
Ying Chen, Jeffrey Lynn, Jiying Li, G. J. Li, G. F. Chen, J. L. Luo, N. L. Wang, Pengcheng Dai, Clarnia dela Cruz, H. A. Mook
Polarized and unpolarized neutron diffraction measurements have been carried out to investigate the iron magnetic order in undoped NdOFeAs. Antiferromagnetic order is observed below 141(6) K, which is in close proximity to the structural distortion

Ferromagnetism in CuO-ZnO multilayers

July 28, 2008
Author(s)
C. Sudakar, K. Pradmanabhan, R Naik, G Lawes, Brian Kirby, Sanjiv Kumar, V. M. Naik
We investigated the magnetic properties of CuO–ZnO heterostructures to elucidate the origin of the ferromagnetic signature in Cu doped ZnO. The CuO and ZnO layer thickness were varied from 15 to 150 nm and from 70 to 350 nm⁠, respectively. Rutherford

Unconventional spin glass behavior in the pyrochlore Mn2Sb2O7

July 9, 2008
Author(s)
H. D. Zhou, C. R. Wiebe, A. Harter, Naresh S. Dalal, Jason Gardner
The new pyrochlore Mn2Sb2O7 has been synthesized via a low-temperature method to retain cubic Fd2m symmetry. The resulting material has an unconventional spin glass state at TSG∼41 K, in the absence of detectable site disorder or a structural phase
Displaying 801 - 825 of 910
Was this page helpful?