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arXiv · 1009.4121

Singular non-ordering susceptibility at a Pomeranchuk instability

Hiroyuki Yamase·Pawel Jakubczyk
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Abstract

We study magnetic susceptibilities of two-dimensional itinerant electron systems exhibiting symmetry-breaking Fermi surface distortions, the so-called d-wave Pomeranchuk instability, in a magnetic field. In a pure forward scattering model, the longitudinal susceptibility chi^{zz} is found to exhibit a jump at a critical point. The magnitude of this jump diverges at a tricritical point. When scattering processes involving finite momentum transfers are allowed for, chi^{zz} is expected to diverge also at a critical point. The system displays multiple critical fluctuations. We argue that the features of chi^{zz} are general properties associated with singularities of a non-ordering susceptibility, leading to implications for a variety of materials including Sr_3Ru_2O_7.

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Hiroyuki Yamase, Pawel Jakubczyk. 2010-09-21. Singular non-ordering susceptibility at a Pomeranchuk instability. https://doi.org/10.1103/physrevb.82.155119

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