Science Highlights

These monthly highlights, selected by MagLab Director Greg Boebinger, represent the most promising and cutting-edge research underway in the lab’s seven user facilities.

15 September 2013

Observation of Single-File Diffusion in Dipeptide Nanotubes

Researchers using pulsed field gradient NMR at the AMRIS facility found clear evidence for molecular single file diffusion of xenon gas confined inside model nanotube systems.

15 September 2013

Quantum Hall Effect in Hydrogenated Graphene

Using the 45T hybrid magnet, researchers uncover the quantum Hall effect in hydrogenated graphene.

15 August 2013

Oxypnictide SmFeAs(O,F) Superconductor: A Candidate for High-field Magnet Applications

Researchers find high critical current density in the recently discovered oxypnictide superconductor SmFeAs(O,F), raising hopes for potential electronics applications.

15 August 2013

Giant Ising-Type Magnetic Anisotropy in Trigonal Bipyramidal Ni(II) Complexes

Research suggests that anisotropy in the high-symmetry coordination environment of Ni(II) complex is an order of magnitude larger than any previously known.

15 July 2013

Quantum Spin Ice: Pyrochlore Quantum Magnet Tb2Ti2O7 at Ultra-Low Temperatures

New research at the lab’s High B/T facility supports the proposal that the disordered ground state of terbium titanate is a quantum spin ice.

15 June 2013

In vivo Chlorine and Sodium MRI of Rat Brain at 21.1 T

Using the lab’s 21 tesla magnet to image chlorine in the brain, researchers explore new ways to track tumor growth.

5 June 2013

Creating a Pseudo-Atomic Model of the COPII Cage

Using a novel combination of techniques, scientists researching the COPII protein created a pseudo-atomic model of the COPII cage, gaining a better understanding of how its 96 subunits fit together.

5 June 2013

Hofstadter’s Butterfly in Moiré Superlattices

Using the 45 tesla hybrid magnet, researchers at the MagLab observed the long-predicted but never-before-seen fractal known as the Hofstadter butterfly. This work enriches our understanding of the basic physics of electrons in a magnetic field and opens a new route for exploring the role of topology in condensed matter systems.

5 June 2013

Massive Dirac Fermions and Hofstadter Butterfly in a van der Waals Heterostructure

Thanks to conditions created by the MagLab’s 45 tesla hybrid magnet, scientists have made a technological breakthrough on graphene: When they placed it on top of hexagonal boron nitride, graphene became a semiconductor.

5 June 2013

Magnetic Field-Induced Delocalized to Localized Transformation in GaAs:N

Using optical spectroscopy and the MagLab’s unique 60 tesla long-pulse magnet in Los Alamos, scientists have shown how nitrogen dopant atoms in gallium arsenide (GaAs) can form extended “supercluster” states or can break up into localized nitrogen clusters. Nitrogen-doped GaAs (GaAs1-xNx) is a semiconductor alloy with potential applications for a wide range of energy-related applications such as photovoltaics.

15 May 2013

Topology of the Cell Metabolome by NMR

Using a novel NMR approach, scientists characterize the metabolome of E. coli cells, determining 112 topologies of unique metabolites from a single sample.

15 May 2013

Emergence of Superconductivity from the Insulating State in La2-xSrxCuO4

Research on La2-xSrxCuO4 provides a new perspective on the mechanism for the superconductor-insulator transition in cuprates, one of the key questions in condensed matter physics.

15 May 2013

1.5-mm High Temperature Superconducting NMR Probe Optimized for 13C

A new 1.5-mm high-temperature superconducting probe designed to detect carbon 13 will significantly enhance studies in natural products and metabolomics.

15 May 2013

Transition From Slow-moving Abrikosov Vortices to Fast-moving Josephson Vortices in an Iron Superconductor

Josephson vortices were unexpectedly observed in the high-temperature iron superconductor SmFeAs(O,F), despite the material’s low electronic anisotropy. This development is important for the future deployment in high-Tc cable technology.

15 April 2013

High-Frequency and -Field EPR Detection of a Di-radical Intermediate

This work defines a new mechanism for radical-mediated catalysis of a protein substrate, and has broad implications for applied biocatalysis and for understanding oxidative protein modification during oxidative stress.

15 April 2013

Quench Protection for the 32 T All-Superconducting Magnet

A prototype high-temperature superconducting coil for the 32 T all-superconducting magnet was constructed with YBCO tape and successfully tested in the large-bore resistive magnet at the MagLab.

15 April 2013

Artificial and Self-assembled Vortex-pinning Centers in Superconducting Ba(Fe1-xCox)2As2 Thin Films

Here we study the microstructural and transport properties of Co-Ba122 thin films in which secondary non-superconducting phases have been introduced during film growth in two different ways: first by using a Co-Ba122 target with a small amount of oxygen, second by alternating two different targets: a clean CoBa122 and an undoped Ba122 target.

15 February 2013

Magnetic Structure and Magneto–electric Coupling in Multiferroics

Multiferroics — “Spintronics without heat” — coupled ferromagnetism and ferroelectricity can provide a new class of functional materials for needed applications including magnetic sensing, data storage and manipulation, high–frequency and high–power electronics, and energy savings.

15 February 2013

Characterization of Pine Pellet and Peanut Hull Pyrolysis Bio-Oils by Negative-Ion Electrospray Ionization FT&-ICR Mass Spectrometry

Pyrolysis of solid biomass, in this case pine pellets and peanut hulls, generates a hydrocarbon-rich liquid product (bio-oil) consisting of oily and aqueous phases. Here, each phase is characterized by negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) to yield unique chemical formulas for thousands of compounds.

15 January 2013

Quantum Oscillations in a Candidate Topological Superconductor, a Copper-doped Topological Insulator: Cu1/4Bi2Se3

A superconducting ground state has been observed at T < 3.8 K in copper-doped Bi2Se3 single crystals. Topological superconductivity is predicted in this material, assuming the superconducting electrons follow the linear energy-momentum dispersion (Dirac-like) seen in graphene and other materials of current interest. However, this presumption had not yet been confirmed by quantum oscillation measurements.

Page 2 of 2