J. R. Stewart

Scale-free antiferromagnetic fluctuations in the s = 1/2 kagome antiferromagnet herbertsmithite.

Neutron spectroscopy and diffuse neutron scattering on herbertsmithite [ZnCu(3)(OH)(6)Cl(2)], a near-ideal realization of the s=1/2 kagome antiferromagnet, reveal the hallmark property of a quantum spin liquid: instantaneous short-ranged antiferromagnetic correlations in the absence of a time-averaged ordered moment. These dynamic antiferromagnetic correlations are weakly dependent of neutron-energy transfer and temperature, and persist up to 25 meV and 120 K. At low energy transfers a shift of the magnetic scattering to low Q is observed with increasing temperature, providing evidence of gapless spinons. It is argued that these observations provide important evidence in favor of resonating-valence-bond theories of (doped) Mott insulators.

Statics and dynamics of the highly correlated spin ice Ho2Ge2O7

The pyrochlore Ho

Pair correlations, short-range order, and dispersive excitations in the quasi-kagome quantum magnet volborthite

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Competing 4 f-electron dynamics in Ce(Ru1-xFex)(2)Al-10 (0

Ge

Magnetic excitations in EuCu2(SixGe1−x)2: from mixed valence towards magnetism

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Spin dynamics, short range order and spin freezing in Y0.5Ca0.5BaCo4O7

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Magnetic short-range order in β-Mn1−xCox

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Neutron scattering and μSR investigations of the low temperature state of LuCuGaO4

is a new highly correlated spin ice material. Physical property measurements, including x-ray diffraction, dc susceptibility, and ac susceptibility, confirm that it shares the distinctive characteristics of other known spin ices. Polarized neutron scattering measurements on a powder sample, combined with reverse Monte Carlo (RMC) refinements, give unique information about the spin ice state in Ho

Slow and static spin correlations in Dy2 + xTi2 − xO7 − δ

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Structural and dynamical study of moment localization in β-Mn_{1−x}In_{x}

Ge