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arXiv · 1004.3300

Saturation field of frustrated chain cuprates: broad regions of predominant interchain coupling

Abstract

An efficient and precise thermodynamic method to extract the interchain coupling (IC) of spatially anisotropic 2D or 3D spin-1/2 systems from their empirical saturation field H_s (T=0) is proposed. Using density-matrix renormalization group, hard-core boson, and spin-wave theory we study how H_s is affected by an antiferromagnetic (AFM) IC between frustrated chains described in the J_1-J_2-spin model with ferromagnetic 1st and AFM 2nd neighbor in-chain exchange. A complex 3D-phase diagram has been found. For Li2CuO2 and Y2Ca2Cu5O10, we show that H_s is solely determined by the IC and predict H_s approx 61 T for the latter.Using H_s approx 55 T from our high-field pulsed measurements one reads out a weak IC for Li2CuO2 close to that from neutron scattering.

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S. Nishimoto, S. -L. Drechsler, R. O. Kuzian, J. van den Brink, J. Richter, W. E. A. Lorenz, Y. Skourski, R. Klingeler, B. Buechner. 2011-04-05. Saturation field of frustrated chain cuprates: broad regions of predominant interchain coupling. https://doi.org/10.1103/physrevlett.107.097201

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