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Magnetic field-tuned quantum critical point in CeAuSb_2

L. Balicas·S. Nakatsuji·H. Lee·P. Schlottmann·T. P. Murphy·Z. Fisk
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Abstract

Transport, magnetic and thermal properties at high magnetic fields (H) and low temperatures (T) of the heavy fermion compound CeAuSb_2 are reported. At H=0 this layered system exhibits antiferromagnetic order below T_N = 6 K. Applying B along the inter-plane direction, leads to a continuous suppression of T_N and a quantum critical point at H_c ~ 5.4 T. Although it exhibits Fermi liquid behavior within the Neel phase, in the paramagnetic state the fluctuations associated with H_c give rise to unconventional behavior in the resistivity (sub-linear in T) and to a TlnT dependence in the magnetic contribution to the specific heat. For H > H_c and low T the electrical resistivity exhibits an unusual T^3-dependence.

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L. Balicas, S. Nakatsuji, H. Lee, P. Schlottmann, T. P. Murphy, Z. Fisk. 2004-11-23. Magnetic field-tuned quantum critical point in CeAuSb_2. https://doi.org/10.1103/physrevb.72.064422

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