Magnetic-field-induced crossover from non-Fermi to Fermi liquid at the quantum critical point of YbCu&lt;sub&gt;5–&lt;em&gt;x&lt;/em&gt;&lt;/sub&gt;Au&lt;sub&gt;&lt;em&gt;x&lt;/em&gt;&lt;/sub&gt;

Carretta, P.; Pasero, R.; Giovannini, M.; Baines, C.

doi:10.1103/PhysRevB.79.020401

Magnetic-field-induced crossover from non-Fermi to Fermi liquid at the quantum critical point of YbCu_5–xAu_x

Carretta P, Pasero R, Giovannini M & Baines C

Citation

Carretta, P., Pasero, R., Giovannini, M., & Baines, C. (2009). Magnetic-field-induced crossover from non-Fermi to Fermi liquid at the quantum critical point of YbCu_5–xAu_x. Physical Review B, 79(2), 020401(R) (4 pp.). https://doi.org/10.1103/PhysRevB.79.020401

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:17237

The temperature (T) dependence of the muon and ⁶³Cu nuclear spin-lattice relaxation rates 1/T₁ in YbCu_4.4Au_0.6 is reported over nearly four decades. It is shown that for T→0 1/T₁ diverges following the behavior predicted by the self-consistent renormalization (SCR) theory for a ferromagnetic quantum critical point. On the other hand, the static uniform susceptibility χ_s is observed to diverge as T^–2/3 and 1/T₁T^∝χ²_s, a behavior which is not accounted for by SCR theory. The application of a magnetic field H is observed to induce a crossover to a Fermi-liquid behavior and for T→0 1/T₁ is found to obey the scaling law 1/T₁(H) = 1/T₁(0)[1+(μ_BH/k_BT)²]^–1.