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Cu nuclear spin-spin coupling in the dimer singlet state in SrCu2(BO3)2

K. Kodama·J. Yamazaki·M. Takigawa·H. Kageyama·K. Onizuka·Y. Ueda
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Abstract

We report results of nuclear magnetic resonance (NMR) experiments in SrCu2(BO3)2, a quasi two-dimensional spin system with a singlet ground state. When magnetic field is applied along the c-axis, each of the quadrupole split Cu resonance lines splits further into four lines. The spin-echo intensity for some of the split lines oscillates against the separation time between the pai/2 and the pai rf-pulses. These phenomena are due to strong nuclear spin-spin coupling mediated by the electronic spin system, which exists only within a pair of nuclei. Thus the results provides direct evidence for the dimer singlet gorund state in this material.

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K. Kodama, J. Yamazaki, M. Takigawa, H. Kageyama, K. Onizuka, Y. Ueda. 2002-03-21. Cu nuclear spin-spin coupling in the dimer singlet state in SrCu2(BO3)2. https://doi.org/10.1088/0953-8984%2F14%2F17%2F101

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