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arXiv · 0705.4099

Theory of the nodal nematic quantum phase transition in superconductors

Eun-Ah Kim·Michael J. Lawler·Paul Oreto·Subir Sachdev·Eduardo Fradkin·Steven A. Kivelson
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Abstract

We study the character of an Ising nematic quantum phase transition (QPT) deep inside a d-wave superconducting state with nodal quasiparticles in a two-dimensional tetragonal crystal. We find that, within a 1/N expansion, the transition is continuous. To leading order in 1/N, quantum fluctuations enhance the dispersion anisotropy of the nodal excitations, and cause strong scattering which critically broadens the quasiparticle (qp) peaks in the spectral function, except in a narrow wedge in momentum space near the Fermi surface where the qp's remain sharp. We also consider the possible existence of a nematic glass phase in the presence of weak disorder. Some possible implications for cuprate physics are also discussed.

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Eun-Ah Kim, Michael J. Lawler, Paul Oreto, Subir Sachdev, Eduardo Fradkin, Steven A. Kivelson. 2008-05-21. Theory of the nodal nematic quantum phase transition in superconductors. https://doi.org/10.1103/physrevb.77.184514

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