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Spin dynamics of $Yb Rh_2 Si_2$ observed by Electron Spin Resonance

J. Sichelschmidt·J. Wykhoff·H. -A. Krug von Nidda·J. Ferstl·C. Geibel·F. Steglich
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Abstract

Below the Kondo temperature $T_{\rm K}$ electron spin resonance (ESR) usually is not observable from the Kondo-ion itself because the characteristic spin fluctuation energy results in a huge width of the ESR line. The heavy fermion metal YbRh$_{2}$Si$_{2}$ seems to be an exceptional case where definite ESR spectra show characteristic properties of the Kondo-ion Yb$^{3+}$ well \textit{below} $T_{\rm K}$. We found that the spin dynamics of YbRh$_{2}$Si$_{2}$, as determined by its ESR relaxation, is spatially characterized by an anisotropy of the zero temperature residual relaxation only.

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J. Sichelschmidt, J. Wykhoff, H. -A. Krug von Nidda, J. Ferstl, C. Geibel, F. Steglich. 2006-09-01. Spin dynamics of $Yb Rh_2 Si_2$ observed by Electron Spin Resonance. https://doi.org/10.1088/0953-8984%2F19%2F11%2F116204

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