Effect of disorder on charge-density wave and superconducting order in the half-filled attractive Hubbard model
- Physics Department, University of California, Davis, California 95616 (United States)
The half-filled attractive Hubbard model exhibits a simultaneous charge-density wave and superconducting order in its ground state. In this paper we use approximation-free quantum Monte Carlo techniques to explore the effect of disorder in the site energies on this degeneracy. We find that superconducting order survives randomness out to a critical amount of disorder, but charge ordering is immediately destroyed. This settles the issue as to whether disordered site energies, which do not break time-reversal invariance, can destroy pairing correlations. We also locate the precise ratio of disorder to bandwidth required for the disorder-driven transition from the superconducting state. We explore the validity of a strong-coupling picture which maps the system onto a Heisenberg model in a random magnetic field. {copyright} {ital 1997} {ital The American Physical Society}
- OSTI ID:
- 470850
- Journal Information:
- Physical Review, B: Condensed Matter, Vol. 55, Issue 2; Other Information: PBD: Jan 1997
- Country of Publication:
- United States
- Language:
- English
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