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ESR study of (Sr,La,Ca)_{14}Cu_{24}O_{41}

V. Kataev·K. -Y. Choi·M. Grueninger·U. Ammerahl·B. Buechner·A. Freimuth·A. Revcolevschi
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Abstract

We report an electron spin resonance (ESR) study of single crystals of the spin-chain spin-ladder compound (Sr,La,Ca)_{14}Cu_{24}O_{41}. The data suggest that in intrinsically hole doped Sr_{14-x}Ca_xCu_{24}O_{41} only a small amount of holes is transferred from the chains to the ladders with increasing x, resulting in a crossover from spin dimerized to uniform spin chains. In the samples of La_{14-x}Ca_xCu_{24}O_{41} with reduced hole content a very broad signal is observed in the paramagnetic state, indicative of a surprisingly strong anisotropy of the nearest neighbor exchange in the chains.

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V. Kataev, K. -Y. Choi, M. Grueninger, U. Ammerahl, B. Buechner, A. Freimuth, A. Revcolevschi. 2001-08-30. ESR study of (Sr,La,Ca)_{14}Cu_{24}O_{41}. https://doi.org/10.1016/s0921-4526(01)01288-1

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