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Quantum Critical Point of Itinerant Antiferromagnet in Heavy Fermion

Hiroaki Kadowaki·Yoshikazu Tabata·Masugu Sato·Naofumi Aso·Stephane Raymond·Shuzo Kawarazaki
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Abstract

A quantum critical point (QCP) of the heavy fermion Ce(Ru_{1-x}Rh_x)_2Si_2 (x = 0, 0.03) has been studied by single-crystalline neutron scattering. By accurately measuring the dynamical susceptibility at the antiferromagnetic wave vector k_3 = 0.35 c^*, we have shown that the energy width Gamma(k_3), i.e., inverse correlation time, depends on temperature as Gamma(k_3) = c_1 + c_2 T^{3/2 +- 0.1}, where c_1 and c_2 are x dependent constants, in a low temperature range. This critical exponent 3/2 +- 0.1 proves that the QCP is controlled by that of the itinerant antiferromagnet.

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Hiroaki Kadowaki, Yoshikazu Tabata, Masugu Sato, Naofumi Aso, Stephane Raymond, Shuzo Kawarazaki. 2005-12-17. Quantum Critical Point of Itinerant Antiferromagnet in Heavy Fermion. https://doi.org/10.1103/physrevlett.96.016401

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