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Strong correlation induced charge localization in antiferromagnets.

ABSTRACT: The fate of a hole injected in an antiferromagnet is an outstanding issue of strongly correlated physics. It provides important insights into doped Mott insulators closely related to high-temperature superconductivity. Here, we report a systematic numerical study of t-J ladder systems based on the density matrix renormalization group. It reveals a surprising result for the single hole's motion in an otherwise well-understood undoped system. Specifically, we find that the common belief of quasiparticle picture is invalidated by the self-localization of the doped hole. In contrast to Anderson localization caused by disorders, the charge localization discovered here is an entirely new phenomenon purely of strong correlation origin. It results from destructive quantum interference of novel signs picked up by the hole, and since the same effect is of a generic feature of doped Mott physics, our findings unveil a new paradigm which may go beyond the single hole doped system.

SUBMITTER: Zhu Z

PROVIDER: S-EPMC3761229 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Strong correlation induced charge localization in antiferromagnets.

Zhu Zheng Z Jiang Hong-Chen HC Qi Yang Y Tian Chushun C Weng Zheng-Yu ZY

Scientific reports 20130101

The fate of a hole injected in an antiferromagnet is an outstanding issue of strongly correlated physics. It provides important insights into doped Mott insulators closely related to high-temperature superconductivity. Here, we report a systematic numerical study of t-J ladder systems based on the density matrix renormalization group. It reveals a surprising result for the single hole's motion in an otherwise well-understood undoped system. Specifically, we find that the common belief of quasipa ...[more]

PMID: 24002668

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