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arXiv · 1204.0333

Semiclassical Approach to Competing Orders in Two-leg Spin Ladder with Ring-Exchange

K. Totsuka·P. Lecheminant·S. Capponi
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Abstract

We investigate the competition between different orders in the two-leg spin ladder with a ring-exchange interaction by means of a bosonic approach. The latter is defined in terms of spin-1 hardcore bosons which treat the N\'eel and vector chirality order parameters on an equal footing. A semiclassical approach of the resulting model describes the phases of the two-leg spin ladder with a ring-exchange. In particular, we derive the low-energy effective actions which govern the physical properties of the rung-singlet and dominant vector chirality phases. As a by-product of our approach, we reveal the mutual induction phenomenon between spin and chirality with, for instance, the emergence of a vector-chirality phase from the application of a magnetic field in bilayer systems coupled by four-spin exchange interactions.

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K. Totsuka, P. Lecheminant, S. Capponi. 2012-04-02. Semiclassical Approach to Competing Orders in Two-leg Spin Ladder with Ring-Exchange. https://doi.org/10.1103/physrevb.86.014435

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