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Field-induced phase transition in the periodic Anderson model

Takuma Ohashi·Akihisa Koga·Sei-ichiro Suga·Norio Kawakami
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Abstract

We investigate the effect of magnetic fields on a Kondo insulator by using the periodic Anderson model. The analysis by dynamical mean field theory combined with quantum Monte Carlo simulations reveals that the magnetic field drives the Kondo insulator to a transverse antiferromagnetic insulator at low temperatures. We calculate the staggered spin susceptibility and find its divergence signaling the antiferromagnetic instability. Further investigation of the spin correlation functions and the magnetization process clarifies how the magnetic field suppresses the Kondo singlet formation and induces the transverse antiferromagnetic ordering.

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Takuma Ohashi, Akihisa Koga, Sei-ichiro Suga, Norio Kawakami. 2004-07-20. Field-induced phase transition in the periodic Anderson model. https://doi.org/10.1016/j.physb.2005.01.211

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