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Register a new userAC Wien effect in spin ice, manifest in non-linear non-equilibrium susceptibility
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Added by
Vojt\\v{e}ch Kaiser
Publication date
2014
fields
Physics
and research's language is
English
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We predict the non-linear non-equilibrium response of a magnetolyte, the Coulomb fluid of magnetic monopoles in spin ice. This involves an increase of the monopole density due to the second Wien effect---a universal and robust enhancement for Coulomb systems in an external field---which in turn speeds up the magnetization dynamics, manifest in a non-linear susceptibility. Along the way, we gain new insights into the AC version of the classic Wien effect. One striking discovery is that of a frequency window where the Wien effect for magnetolyte and electrolyte are indistinguishable, with the former exhibiting perfect symmetry between the charges. In addition, we find a new low-frequency regime where the growing magnetization counteracts the Wien effect. We discuss for what parameters best to observe the AC Wien effect in Dy$_2$Ti$_2$O$_7$.
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