Low frequency spin dynamics in the quantum magnet copper pyrazine dinitrate
| Autor: | Kuehne, H., Guenther, M., Grossjohann, S., Brenig, W., Litterst, F. J., Reyes, A. P., Kuhns, P. L., Turnbull, M. M., Landee, C. P., Klauss, H. -H. |
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| Rok vydání: | 2010 |
| Předmět: | |
| Zdroj: | Physica Status Solidi B 247, 671 (2010) |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1002/pssb.200983077 |
| Popis: | The S=1/2 antiferromagnetic Heisenberg chain exhibits a magnetic field driven quantum critical point. We study the low frequency spin dynamics in copper pyrazine dinitrate (CuPzN), a realization of this model system of quantum magnetism, by means of $^{13}$C-NMR spectroscopy. Measurements of the nuclear spin-lattice relaxation rate $T_1^{-1}$ in the vicinity of the saturation field are compared with quantum Monte Carlo calculations of the dynamic structure factor. Both show a strong divergence of low energy excitations at temperatures in the quantum regime. The analysis of the anisotropic $T_1^{-1}$-rates and frequency shifts allows one to disentangle the contributions from transverse and longitudinal spin fluctuations for a selective study and to determine the transfer of delocalized spin moments from copper to the neighboring nitrogen atoms. Comment: 5 pages, 6 figures, published in Physica Status Solidi B |
| Databáze: | arXiv |
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