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arXiv · 1010.2315

Magnetically Robust Non-Fermi Liquid Behavior in Heavy Fermion Systems with f^2-Configuration: Competition between Crystalline-Electric-Field and Kondo-Yosida Singlets

Shinya Nishiyama·Hiroyasu Matsuura·Kazumasa Miyake
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Abstract

We study a magnetic field effect on the Non-Fermi Liquid (NFL) which arises around the quantum critical point (QCP) due to the competition between the f^2-crystalline-electric-field singlet and the Kondo-Yosida singlet states by using the numerical renormalization ground method. We show the characteristic temperature T_F^*, corresponding to a peak of a specific heat, is not affected by the magnetic field up to H_z^* which is determined by the distance from the QCP or characteristic energy scales of each singlet states. As a result, in the vicinity of QCP, there are parameter regions where the NFL is robust against the magnetic field, at an observable temperature range T > T_F^*, up to H_z^* which is far larger than T_F^* and less than min(T_{K2}, $Delta).

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Shinya Nishiyama, Hiroyasu Matsuura, Kazumasa Miyake. 2010-10-12. Magnetically Robust Non-Fermi Liquid Behavior in Heavy Fermion Systems with f^2-Configuration: Competition between Crystalline-Electric-Field and Kondo-Yosida Singlets. https://doi.org/10.1143/jpsj.79.104711

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