Interference of nematic quantum critical quasiparticles: a route to the octet model

Eun-Ah Kim; Michael J. Lawler

doi:10.1103/physrevb.81.132501

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arXiv · 0811.2242

Interference of nematic quantum critical quasiparticles: a route to the octet model

Eun-Ah Kim·Michael J. Lawler

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Abstract

Repeated observations of inhomogeneity in cuperate superconductors[1-5] make one immediately question the existance of coherent quasiparticles(qp's) and the applicability of a momentum space picture. Yet, obversations of interference effects[6-9] suggest that the qp's maintain a remarkable coherence under special circumstances. In particular, quasi-particle interference (QPI) imaging using scanning tunneling spectroscopy revealed a highly unusual form of coherence: accumulation of coherence only at special points in momentum space with a particular energy dispersion[5-7]. Here we show that nematic quantum critical fluctuations[10], combined with the known extreme velocity anisotropy[11] provide a natural mechanism for the accumulation of coherence at those special points. Our results raise the intriguing question of whether the nematic fluctuations provide the unique mechanism for such a phenomenon.

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Eun-Ah Kim, Michael J. Lawler. 2008-11-13. Interference of nematic quantum critical quasiparticles: a route to the octet model. https://doi.org/10.1103/physrevb.81.132501

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