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arXiv · 1509.01022

Electron Spin Resonance in a Spin-1/2 Heisenberg Strong-rung Ladder

A. N. Ponomaryov·M. Ozerov·L. Zviagina·J. Wosnitza·K. Yu. Povarov·F. Xiao·A. Zheludev·C. Landee·E. Čižmár·A. A. Zvyagin·S. A. Zvyagin
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Abstract

Cu(C$_8$H$_6$N$_2$)Cl$_2$, a strong-rung spin-1/2 Heisenberg ladder compound, is probed by means of electron spin resonance (ESR) spectroscopy in the field-induced gapless phase above $H_{c1}$. The temperature dependence of the ESR linewidth is analyzed in the quantum field theory framework, suggesting that the anisotropy of magnetic interactions plays a crucial role, determining the peculiar low-temperature ESR linewidth behavior. In particular, it is argued that the uniform Dzyaloshinskii-Moriya interaction (which is allowed on the bonds along the ladder legs) can be the source of this behavior in Cu(C$_8$H$_6$N$_2$)Cl$_2$.

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A. N. Ponomaryov, M. Ozerov, L. Zviagina, J. Wosnitza, K. Yu. Povarov, F. Xiao, A. Zheludev, C. Landee, E. Čižmár, A. A. Zvyagin, S. A. Zvyagin. 2015-09-03. Electron Spin Resonance in a Spin-1/2 Heisenberg Strong-rung Ladder. https://doi.org/10.1103/physrevb.93.134416

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