Point-contact properties of non-Fermi liquid compounds YbCu5−xAlx ( and 1.6) in the vicinity of QCP

Suppression of asymmetric differential resistance in the non-Fermi-liquid systemYbCu5−xAlxPristáš1, Reiffers2, Bauer3 et al. 2008Phys. Rev. B105160View full textAdd to dashboardCite

“…5 Presented analysis and high magnetic-field measurements confirm our previously published data. 6,7 We have demonstrated that our spectra are not in the thermal regime, and thus, they are bringing the information about scattering of conduction electrons. The maximum in differential resistance close to 1 mV reflects the increasing magnitude of scattering of conduction electrons.…”

“…This different type of asymmetry is connected with the NFL behavior at the QCP. 6,7 The application of a magnetic field strongly changed the shape of the differential resistance, showing a recovering of the Fermi-liquid ͑FL͒ behavior characteristic for Kondo compounds. 8,9 The behavior of PC dependencies of other concentrations differs from the one at the critical concentration.…”

“…5 Our previous PC experiments on YbCu 5−x Al x ͑x = 1.3-1.6͒ have been performed at temperatures down to 1.5 K and in magnetic fields up to 6 T in the heterocontact configuration using a Cu or Pt counterelectrode. 6,7 The differential resistance dV / dI͑V͒ as a function of the applied voltage V revealed an asymmetric behavior. In the case of x cr = 1.5 we have observed a maximum at 1.3 mV in only one voltage polarity.…”