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arXiv · 1401.4665

Formation of gapless triplets in the bond-doped spin-gap antiferromagnet (C$_4$H$_{12}$N$_2$)(Cu$_2$Cl$_6$)

V. N. Glazkov·G. Skoblin·D. Hüvonen·T. S. Yankova·A. Zheludev
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Abstract

We report results of an electron spin resonance (ESR) study of a spin-gap antiferromagnet (C$_4$H$_{12}$N$_2$)(Cu$_2$Cl$_6$) (nicknamed PHCC) with chlorine ions partially substituted by bromine. We found that up to 10% of nominal doping the contribution of the random defects to the absorption spectra remains at about 0.1% per copper ion, almost the same as in the pure system. Instead, a particular kind of ESR absorption corresponding to gapless S=1 triplets is observed at low temperatures in samples with high nominal bromine content x>5%. Increase of bromine concentration also leads to the systematic broadening of ESR absorption line indicating reduction of the quasi-particles lifetime.

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V. N. Glazkov, G. Skoblin, D. Hüvonen, T. S. Yankova, A. Zheludev. 2014-11-19. Formation of gapless triplets in the bond-doped spin-gap antiferromagnet (C$_4$H$_{12}$N$_2$)(Cu$_2$Cl$_6$). https://doi.org/10.1088/0953-8984%2F26%2F48%2F486002

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