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arXiv · 1609.06091

Static and Dynamic Magnetic Response of Fragmented Haldane-like Spin Chains in Layered Li3Cu2SbO6

Changhyun Koo·Elena A. Zvereva·Igor L. Shukaev·Michael Richter·Mikhail I. Stratan·Alexander N. Vasiliev·Vladimir B. Nalbandyan·Rüdiger Klingeler
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Abstract

The structure and the magnetic properties of layered Li3Cu2SbO6 are investigated by powder X-ray diffraction, static susceptibility, and electron spin resonance studies up to 330 GHz. The XRD data experimentally verify the space group C2/m with halved unit cell volume in contrast to previously reported C2/c. In addition, the data show significant Li/Cu-intersite exchange. Static magnetic susceptibility and ESR measurements show two magnetic contributions, i.e. quasi-free spins at low-temperature and a spin-gapped magnetic subsystem, with about half of the spins being associated to each subsystem. The data suggest ferromagnetic-antiferromagnetic alternating chains with JFM = -285 K and JAFM = 160 K with a significant amount of Li-defects in the chains. The results are discussed in the scenario of fragmented 1D S = 1 AFM chains with a rather high defect concentration of about 17% and associated S = 1/2 edge states of the resulting finite Haldane chains.

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Changhyun Koo, Elena A. Zvereva, Igor L. Shukaev, Michael Richter, Mikhail I. Stratan, Alexander N. Vasiliev, Vladimir B. Nalbandyan, Rüdiger Klingeler. 2016-09-20. Static and Dynamic Magnetic Response of Fragmented Haldane-like Spin Chains in Layered Li3Cu2SbO6. https://doi.org/10.7566/jpsj.85.084702

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