Publications by authors named "C Niedermayer"

Article Synopsis
  • Electrons at the borders of localization lead to unique states of matter in strongly correlated electron materials, like heavy electron metals, which showcase interesting magnetic behaviors.
  • These phenomena arise from the interplay between localized and itinerant electrons, giving rise to novel states such as unconventional superconductivity and topological states of matter.
  • The researchers simplified the complex Kondo lattice model for the antiferromagnet CeIn by integrating bandstructure calculations with a multi-orbital model, successfully validating their findings through neutron spectroscopy, thus enhancing our understanding of metallic quantum states.
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Control of magnetization and electric polarization is attractive in relation to tailoring materials for data storage and devices such as sensors or antennae. In magnetoelectric materials, these degrees of freedom are closely coupled, allowing polarization to be controlled by a magnetic field, and magnetization by an electric field, but the magnitude of the effect remains a challenge in the case of single-phase magnetoelectrics for applications. We demonstrate that the magnetoelectric properties of the mixed-anisotropy antiferromagnet LiNiFePO are profoundly affected by partial substitution of Ni ions with Fe on the transition metal site.

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We report on the commissioning results of the cold neutron multiplexing secondary spectrometer CAMEA (Continuous Angle Multi-Energy Analysis) at the Swiss Spallation Neutron Source at the Paul Scherrer Institut, Switzerland. CAMEA is optimized for efficient data acquisition of scattered neutrons in the horizontal scattering plane, allowing for detailed and rapid mapping of low-energy excitations under extreme sample environment conditions.

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Natural product methyltransferases (NPMTs) represent an emerging class of enzymes that can be of great use for the structural and functional diversification of bioactive compounds, such as the strategic modification of C-, N-, O- and S-moieties. To assess the activity and the substrate scope of the ever-expanding repertoire of NPMTs, a simple, fast, and robust assay is needed. Here, we report a continuous spectroscopic assay, in which S-adenosyl-L-methionine-dependent methylation is linked to NADH oxidation through the coupled activities of S-adenosyl-L-homocysteine (SAH) deaminase and glutamate dehydrogenase.

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Neutron spectroscopy on the classical triangular-lattice frustrated antiferromagnet h-YMnO_{3} reveals diffuse, gapless magnetic excitations present both far below and above the ordering temperature. The correlation length of the excitations increases as the temperature approaches zero, bearing a strong resemblance to critical scattering. We model the dynamics in the ordered and correlated disordered phase as critical spin correlations in a two-dimensional magnetic state.

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