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Field-induced paramagnons at the metamagnetic transition in Ca1.8Sr0.2RuO4

P. Steffens·Y. Sidis·P. Link·K. Schmalzl·S. Nakatsuji·Y. Maeno·M. Braden
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Abstract

The magnetic excitations in Ca1.8Sr0.2RuO4 were studied across the metamagnetic transition and as a function of temperature using inelastic neutron scattering. At low temperature and low magnetic field the magnetic response is dominated by a complex superposition of incommensurate antiferromagnetic fluctuations. Upon increasing the magnetic field across the metamagnetic ransition, paramagnon and finally well-defined magnon scattering is induced, partially suppressing the incommensurate signals. The high-field phase in Ca1.8Sr0.2RuO4 has, therefore, to be considered as an intrinsically ferromagnetic state stabilized by the magnetic field.

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P. Steffens, Y. Sidis, P. Link, K. Schmalzl, S. Nakatsuji, Y. Maeno, M. Braden. 2007-03-30. Field-induced paramagnons at the metamagnetic transition in Ca1.8Sr0.2RuO4. https://doi.org/10.1103/physrevlett.99.217402

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