ANOMALOUS LOCAL CRITICALITY IN HEAVY FERMION METALS FROM HOLOGRAPHY

作者：Luo M J^*

来源：Modern Physics Letters B, 2014, 28(1): 1450005.

DOI：10.1142/S0217984914500055

• AdS/CFT
• Kondo system
• quantum criticality
• non-Gaussian fixed point

In this paper, we propose a holographic theory to explain a number of anomalous critical phenomena observed in certain heavy fermion metals, e.g. CeCu5.9Au0.1 and YbRh2(Si0.95Ge0.05)(2), which are incompatible with any conventional spin-density-wave quantum critical point theory. We show that the non-Gaussian nature of the fixed point from holography plays an essential role in the physics of these materials near a quantum critical point, which is not in the same universality class of the spin-density-wave type fixed point. The critical spin fluctuations at the non-Gaussian fixed point are strongly anisotropic, localized in spatial directions and critical in temporal direction with critical exponent 2/3 in frequency over temperature dependence at low temperature. The local critical exponent tends to unity which leads to a constant spin relaxation rate in the quantum critical regime at high temperature. The stability of the fixed point is also discussed.

• 出版日期2014-1-10
• 单位清华大学