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Probing the extended non-Fermi liquid regimes of MnSi and Fe

P. Pedrazzini·D. Jaccard·G. Lapertot·J. Flouquet·Y. Inada·H. Kohara·Y. Onuki
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Abstract

Recent studies show that the non-Fermi liquid (NFL) behavior of MnSi and Fe spans over an unexpectedly broad pressure range, between the critical pressure p_c and around 2p_c. In order to determine the extension of their NFL regions, we analyze the evolution of the resistivity rho(T) A(p)T^n at higher pressures. We find that in MnSi the n=3/2 exponent holds below 4.8 GPa=3 p_c, but it increases above that pressure. At 7.2 GPa we observe the low temperature Fermi liquid exponent n=2 whereas for T>1.5 K, n=5/3. Our measurements in Fe show that the NFL behavior rho T^{5/3} extends at least up to 30.5 GPa, above the entire superconducting (SC) region. In the studied pressure range, the onset of the SC transition reduces by a factor 10 down to T_c^onset(30.5 GPa)=0.23 K, while the A-coefficient diminishes monotonically by around 50%.

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P. Pedrazzini, D. Jaccard, G. Lapertot, J. Flouquet, Y. Inada, H. Kohara, Y. Onuki. 2005-09-29. Probing the extended non-Fermi liquid regimes of MnSi and Fe. https://doi.org/10.1016/j.physb.2006.01.062

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