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تسجيل مستخدم جديدElectrodynamic response of Ba(Fe1-xRhx)2As2 across the s+- to s++ order parameter transition
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Most iron-based superconductors are characterized by the s+- symmetry of their order parameter, and are expected to go through a transition to the s++ state if enough disorder is introduced. We previously reported the observation of this transition in Ba(Fe1-xRhx)2As2 through a study of the disorder dependence of the critical temperature and low-temperature London penetration depth. In this paper we report on the analysis of the electrodynamic response of the same sample across the transition and we identify peculiarities in the behaviour of the surface resistance and normal conductivity, that can be considered as traces of the transition itself.
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This work presents 75As NMR spin echo decay rate (1/T2) measurements in Ba(Fe1-xRhx)2As2 superconductors, for 0.041 < x < 0.094. It is shown that 1/T2 increases upon cooling, in the normal phase, suggesting the onset of an unconventional very low-fre
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We studied the doping and temperature (T) dependence of the infrared (IR) response of Ba(Fe1-xCox)2As2 single crystals. We show that a weak band around 1000 cm-1, that was previously interpreted in terms of interaction of the charge carriers with mag
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