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arXiv · 1111.4373

Renormalization-group exponents for superconducting phases in two-leg ladders

Yiwei Cai·Wen-Min Huang·Hsiu-Hau Lin
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Abstract

In previous studies, we proposed a scaling ansatz for electron-electron interactions under renormalization group transformation. With the inclusion of phonon-mediated interactions, we show that the scaling ansatz, characterized by the divergent logarithmic length $l_d$ and a set of renormalization-group exponents, also works rather well. The superconducting phases in a doped two-leg ladder are studied and classified by these renormalization-group exponents as demonstration. Finally, non-trivial constraints among the exponents are derived and explained.

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Yiwei Cai, Wen-Min Huang, Hsiu-Hau Lin. 2011-11-18. Renormalization-group exponents for superconducting phases in two-leg ladders. https://doi.org/10.1103/physrevb.85.134502

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