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Scaling of magnetic fluctuations near a quantum phase transition

A. Schroder·G. Aeppli·E. Bucher·R. Ramazashvili·P. Coleman
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Abstract

We use inelastic neutron scattering to measure the magnetic fluctuations in a single crystal of the heavy fermion alloy CeCu_5.9Au_0.1 close to the antiferromagnetic quantum critical point. The energy and temperature-dependent spectra obey (E/T) scaling at Q near (1,0,0). The neutron data and earlier bulk susceptibility are consistent with the form 1/X ~ f(Q)+(-iE+bT)^a, with an anomalous exponent a=0.8. We confirm the earlier observation of quasi-low dimensionality and show how both the magnetic fluctuations and the thermodynamics can be understood in terms of a quantum Lifshitz point.

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A. Schroder, G. Aeppli, E. Bucher, R. Ramazashvili, P. Coleman. 1998-03-01. Scaling of magnetic fluctuations near a quantum phase transition. https://doi.org/10.1103/physrevlett.80.5623

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