تقرير
$\mu$SR studies of the frustrated quasi-2d square-lattice spin system Cu(Cl,Br)La(Nb,Ta)$_{2}$O$_{7}$: evolution from spin-gap to antiferromagnetic state
| العنوان: | $\mu$SR studies of the frustrated quasi-2d square-lattice spin system Cu(Cl,Br)La(Nb,Ta)$_{2}$O$_{7}$: evolution from spin-gap to antiferromagnetic state |
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| المؤلفون: | Uemura, Y. J., Aczel, A. A., Ajiro, Y., Carlo, J. P., Goko, T., Goldfeld, D. A., Kitada, A., Luke, G. M., MacDougall, G. J., Mihailescu, I. G., Rodriguez, J. A., Russo, P. L., Tsujimoto, Y., Wiebe, C. R., Williams, T. J., Yamamoto, T., Yoshimura, K., Kageyama, H. |
| المصدر: | Phys. Rev. B 80, 174408 (2009) |
| سنة النشر: | 2008 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Strongly Correlated Electrons, Condensed Matter - Superconductivity |
| الوصف: | We report muon spin relaxation ($\mu$SR) and magnetic susceptibility measurements on Cu(Cl,Br)La(Nb,Ta)$_{2}$O$_{7}$, which demonstrate: (a) the absence of static magnetism in (CuCl)LaNb$_{2}$O$_{7}$ down to 15 mK confirming a spin-gapped ground state; (b) phase separation between partial volumes with a spin-gap and static magnetism in (CuCl)La(Nb,Ta)$_{2}$O$_{7}$; (c) history-dependent magnetization in the (Nb,Ta) and (Cl,Br) substitution systems; (d) a uniform long-range collinear antiferromagnetic state in (CuBr)LaNb$_{2}$O$_{7}$; and (e) a decrease of N\'eel temperature with decreasing Br concentration $x$ in Cu(Cl$_{1-x}$Br$_{x}$)LaNb$_{2}$O$_{7}$ with no change in the ordered Cu moment size for $0.33 \leq x \leq 1$. Together with several other $\mu$SR studies of quantum phase transitions in geometrically-frustrated spin systems, the present results reveal that the evolution from a spin-gap to a magnetically ordered state is often associated with phase separation and/or a first order phase transition. Comment: 10 pages 10 color figures; revised from letter paper style to full paper style; Figs. 2, 4, 5, 7c, 10 newly added |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1103/PhysRevB.80.174408 |
| URL الوصول: | http://arxiv.org/abs/0806.2021 |
| رقم الأكسشن: | edsarx.0806.2021 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1103/PhysRevB.80.174408 |
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