Charge ordering in quasi-one-dimensional systems with frustrating interactions

Siddhartha Lal; Mukul S. Laad

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Charge ordering in quasi-one-dimensional systems with frustrating interactions

Siddhartha Lal·Mukul S. Laad

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Abstract

Motivated by the co-existing charge and spin order found in strongly correlated ladder systems, we study an effective pseudospin model on a coupled two-leg ladder. A bosonisation analysis yields a rich phase diagram showing Wigner/Peierls charge order and Neel/dimer spin order. In a broad parameter regime, the orbital antiferromagnetic phase is found to be stable. An intermediate gapless phase of finite width is found to lie in between two charge-ordered gapped phases. Our work is potentially relevant for a unified description of a class of strongly correlated, quarter-filled ladder systems.

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Siddhartha Lal, Mukul S. Laad. 2005-11-18. Charge ordering in quasi-one-dimensional systems with frustrating interactions. https://arxiv.org/abs/cond-mat/0511458

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