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arXiv · 0708.3029

Interplay between field-induced and frustration-induced quantum criticalities in the frustrated two-leg Heisenberg ladder

Brandon W. Ramakko·Mohamed Azzouz
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Abstract

The antiferromagnetic Heisenberg two-leg ladder in the presence of frustration and an external magnetic field is a system that is characterized by two sorts of quantum criticalities, not only one. One criticality is the consequence of intrinsic frustration, and the other one is a result of the external magnetic field. So the behaviour of each of them in the presence of the other deserves to be studied. Using the Jordan-Wigner transformation in dimensions higher than one and bond-mean-field theory we examine the interplay between the field-induced and frustration-induced quantum criticalities in this system. The present work could constitute a prototype for those systems showing multiple, perhaps sometimes competing, quantum criticalities. We calculate several physical quantities like the magnetization and spin susceptibility as functions of field and temperature.

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Brandon W. Ramakko, Mohamed Azzouz. 2007-08-22. Interplay between field-induced and frustration-induced quantum criticalities in the frustrated two-leg Heisenberg ladder. https://doi.org/10.1139/p08-050

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