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arXiv · 1705.06035

Quantum criticality in the coupled two-leg spin ladder Ba2CuTeO6

A. Glamazda·Y. S. Choi·S. -H. Do·S. Lee·P. Lemmens·A. N. Ponomaryov·S. A. Zvyagin·J. Wosnitza·Dita Puspita Sari·I. Watanabe·K. -Y. Choi
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Abstract

We report on zero-field muon spin rotation, electron spin resonance and polarized Raman scattering measurements of the coupled quantum spin ladder Ba2CuTeO6. Zero-field muon spin rotation and electron spin resonance probes disclose a successive crossover from a paramagnetic through a spin-liquid-like into a magnetically ordered state with decreasing temperature. More significantly, the two-magnon Raman response obeys a T-linear scaling relation in its peak energy, linewidth and intensity. This critical scaling behavior presents an experimental signature of proximity to a quantum critical point from an ordered side in Ba2CuTeO6.

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A. Glamazda, Y. S. Choi, S. -H. Do, S. Lee, P. Lemmens, A. N. Ponomaryov, S. A. Zvyagin, J. Wosnitza, Dita Puspita Sari, I. Watanabe, K. -Y. Choi. 2017-05-17. Quantum criticality in the coupled two-leg spin ladder Ba2CuTeO6. https://doi.org/10.1103/physrevb.95.184430

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