JETP Letters

, Volume 96, Issue 6, pp 397–404

Nature of the quantum critical point as disclosed by extraordinary behavior of magnetotransport and the lorentz number in the heavy-fermion metal YbRh2Si2

Authors

    • Petersburg Nuclear Physics Institute
    • Clark Atlanta University
  • A. Z. Msezane
    • Clark Atlanta University
  • K. G. Popov
    • Komi Science Center, Ural DivisionRussian Academy of Sciences
  • J. W. Clark
    • McDonnell Center for the Space Sciences and Department of PhysicsWashington University
  • M. V. Zverev
    • National Research Centre Kurchatov Institute
    • Moscow Institute of Physics and Technology
  • V. A. Khodel
    • McDonnell Center for the Space Sciences and Department of PhysicsWashington University
    • National Research Centre Kurchatov Institute
Article

DOI: 10.1134/S0021364012180105

Cite this article as:
Shaginyan, V.R., Msezane, A.Z., Popov, K.G. et al. Jetp Lett. (2012) 96: 397. doi:10.1134/S0021364012180105

Abstract

Physicists are engaged in vigorous debate on the nature of the quantum critical points (QCP) governing the low-temperature properties of heavy-fermion metals. Recent experimental observations of the much-studied compound YbRh2Si2 in the regime of vanishing temperature incisively probe the nature of its magnetic-field-tuned QCP. The jumps revealed both in the residual resistivity ρ0 and the Hall resistivity RH, along with violation of the Wiedemann-Franz law, provide vital clues to the origin of such non-Fermi-liquid behavior. The empirical facts point unambiguously to association of the observed QCP with a fermion-condensation phase transition. Based on this insight, the resistivities ρ0 and RH are predicted to show jumps at the crossing of the QCP produced by application of a magnetic field, with attendant violation of the Wiedemann-Franz law. It is further demonstrated that experimentally identifiable multiple energy scales are related to the scaling behavior of the effective mass of the quasiparticles responsible for the low-temperature properties of such heavy-fermion metals.

Copyright information

© Pleiades Publishing, Ltd. 2012