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arXiv · 0912.2092

Dynamic cluster quantum Monte Carlo simulations of a two-dimensional Hubbard model with stripe-like charge density wave modulations: Interplay between inhomogeneity and superconductivity

T. A. Maier·G. Alvarez·M. Summers·T. C. Schulthess
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Abstract

Using dynamic cluster quantum Monte Carlo simulations, we study the superconducting behavior of a 1/8 doped two-dimensional Hubbard model with imposed uni-directional stripe-like charge density wave modulation. We find a significant increase of the pairing correlations and critical temperature relative to the homogeneous system when the modulation length-scale is sufficiently large. With a separable form of the irreducible particle-particle vertex, we show that optimized superconductivity is obtained for moderate modulation strength due to a delicate balance between the modulation enhanced pairing interaction, and a concomitant suppression of the bare particle-particle excitations by a modulation reduction of the quasi-particle weight.

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T. A. Maier, G. Alvarez, M. Summers, T. C. Schulthess. 2010-07-13. Dynamic cluster quantum Monte Carlo simulations of a two-dimensional Hubbard model with stripe-like charge density wave modulations: Interplay between inhomogeneity and superconductivity. https://doi.org/10.1103/physrevlett.104.247001

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