# Anomalous Reduction of the Lorenz Ratio at the Quantum Critical Point in YbAgGe

Title | Anomalous Reduction of the Lorenz Ratio at the Quantum Critical Point in YbAgGe |

Publication Type | Journal Article |

Year of Publication | 2013 |

Authors | Dong JK, Tokiwa Y, Bud'ko SL, Canfield PC, Gegenwart P |

Journal Title | Physical Review Letters |

Volume | 110 |

Pages | 176402 |

Date Published | 04 |

Type of Article | Article |

ISBN Number | 0031-9007 |

Accession Number | WOS:000317915200019 |

Keywords | fermi-liquid behavior, heavy fermions, metals, phase-transitions, superconductivity |

Abstract | We report measurements of the electrical and thermal transport on the hexagonal heavy-fermion metal YbAgGe for temperatures T >= 40 mK and in magnetic fields H parallel to ab up to 14 T. This distorted kagome-lattice system displays a series of magnetic states and a quantum critical point at H-c = 4.5 T. The Lorenz ratio L(T)/L-0 displays a marked reduction only close to H-c. A T-linear contribution below 120 mK, present at all different fields, allows us to extrapolate the Lorenz ratio towards T = 0. At the critical field this yields L/L-0 = 0.92 +/- 0.03, suggesting a violation of the Wiedemann-Franz law due to strong inelastic scattering. DOI: 10.1103/PhysRevLett.110.176402 |

URL | <Go to ISI>://WOS:000317915200019 |

DOI | 10.1103/PhysRevLett.110.176402 |