Highlights of research on Sector 6

How Lead-Free Solder (Mis)Behaves under Stress

October 10, 2012

The reliability and longevity of electronics is critical to current telecommunications technology. Research on 6-ID-D is bringing new information about thermal fatigue in environmentally friendly, lead-free solder joints. These studies provide information for making reliability predictions about solder-joint failure in this important new material.

Contact: Thomas Bieler - Michigan State University

Unlikely route to ferroelectricity

May 16, 2012

A new type of ferroelectric, LuO₂Fe₄, has been investigated at the APS by a research team from Julich research center. XAS & XMCD studies on beamline 4-ID-C determined the Fe magnetism and valence, while single crystal x-ray scattering measurements at 6-ID-B & 6-ID-D probed the associated structural and charge ordering.

Contact: Manuel Angst - Forschungszentrum Julich

Searching for Next-Generation Electronic Materials

December 14, 2009

A new class of layered oxide materials discovered thanks to research at the beamline 6-ID-B offers scientists unprecedented opportunities for creating the next generation of electronic devices.

Local Contact: Phil Ryan

Concentration, temperature, and pH dependence of SY aggregates

October 7, 2009

Researchers from Kent State University have used beamline 6-ID-B to measure the positional-order and correlation lengths of collumar agagates of the dye sunset yellow (SY) as functions of temperature, concentration, and ionic content. The average length of aggregates i.e., the number of SY molecules pressent in each column, was found to grow monotonically with concentration while their effective transverse separation decreased. Temperature and concentration dependence of suggests that chromonic aggregation is not an isodesmic process.

Contact: Satyen Kumar - Kent State University

Understanding ferroelectricity in LuFe₂O₄

November 26, 2008

A research team from Oak Ridge National Lab and Forschungszentrum Julich has used beamline 6-ID-B to examine a novel ferroelecticity arising from charge order (CO) in LuFe₂O₄. Long-range CO was found below 320K with a (⅓,⅓, 0) propagation vector corresponding to an antiferroelectric arrangement of polar subunits. At higher temperatures short-range correlations persisted, indicating the presence of a competing (ferroelectric) propagation.

Pressure-Tuning the Quantum Phase Transition in a Model 2-D Magnet

April 11, 2012

Researchers using high-resolution x-ray scattering on beamlines 4-ID-D and 6-ID-B have demonstrated how pressure can be used to dial-in different magnetic states in a two-dimensional magnetic material, SrCu₂(BO₃)₂.

Contacts: Sara Haravifard & Tom Rosenbaum -Univ. of Chicago

High-energy x-ray pattern of icosahedral quasicrystals

January 10, 2010

Researchers using beamline 6-ID-D have confirmed the presence of stable icosahedral quasicrystals in the ScZn binary phase diagram. Diffraction patterns were collected along the five-fold and two-fold axes (figure). Icosahedral symmetry with high perfection was shown to persist over the full bulk sample.

Contact: Andreas Kreyssig - Ames Laboratory

High-energy x-ray studies of Fe-Ga magnetostrictive alloys

June 12, 2008

High energy x-rays have been used to characterize the Ga ordering in magnetostrictive Fe1-xGax from 0<x<0.2. The diffuse scattering in the [H H L] plane shows both short range order (SRO) and thermal diffuse scattering features (figure). A dramatic suppression of magnetostriction near ~20% Ga concentration can be linked rapid growth of SRO clusters just before the onset of long-range chemical order.

Contact: Robert McQueeney - Iowa State University

Surface Orbital 'Roughness' in Colossal Magnetoresistive Oxide

November 21, 2007

Is electronic behavior, such as charge, orbital, or spin order, different at a material’s surface or the interface between two materials compared to the bulk of the material? Researchers using beamline 6-ID-B at the APS have found important new information about these behaviors.