Volume 114, Number 6, June 2016
|Number of page(s)||6|
|Section||Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties|
|Published online||25 July 2016|
The route to magnetic order in the spin-1/2 kagome Heisenberg antiferromagnet: The role of interlayer coupling
Institut für Theoretische Physik, Universität Magdeburg - 39016 Magdeburg, Germany
Received: 11 April 2016
Accepted: 6 July 2016
While the existence of a spin-liquid ground state of the spin-1/2 kagome Heisenberg antiferromagnet (KHAF) is well established, the discussion of the effect of an interlayer coupling (ILC) by controlled theoretical approaches is still lacking. Here we study this problem by using the coupled-cluster method to high orders of approximation. We consider a stacked KHAF with a perpendicular ILC , where we study ferro- as well as antiferromagnetic . We find that the spin-liquid ground state (GS) persists until relatively large strengths of the ILC. Only if the strength of the ILC exceeds about 15% of the intralayer coupling the spin-liquid phase gives way for q = 0 magnetic long-range order, where the transition between both phases is continuous and the critical strength of the ILC, , is almost independent of the sign of . Thus, by contrast to the quantum GS selection of the strictly two-dimensional KHAF at large spin s, the ILC leads first to a selection of the q = 0 GS. Only at larger the ILC drives a first-order transition to the long-range ordered GS. As a result, the stacked spin-1/2 KHAF exhibits a rich GS phase diagram with two continuous and two discontinuous transitions driven by the ILC.
PACS: 75.10.Jm – Quantized spin models, including quantum spin frustration / 75.10.Kt – Quantum spin liquids, valence bond phases and related phenomena / 75.40.Mg – Numerical simulation studies
© EPLA, 2016
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.