Fractional spin textures in the frustrated magnet SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$

Arnab Sen; Kedar Damle; Roderich Moessner

doi:10.1103/physrevlett.106.127203

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arXiv · 1007.4507

Fractional spin textures in the frustrated magnet SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$

Arnab Sen·Kedar Damle·Roderich Moessner

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Abstract

We consider the archetypal frustrated antiferromagnet SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$ in its well-known spin-liquid state, and demonstrate that a Cr$^{3+}$ spin $S=3/2$ ion in direct proximity to a pair of vacancies (in disordered $p<1$ samples) is cloaked by a spatially extended spin texture that encodes the correlations of the parent spin-liquid. In this spin-liquid regime, the combined object has a magnetic response identical to a classical spin of length $S/2 = 3/4$, which dominates over the small intrinsic susceptibility of the pure system. This fractional-spin texture leaves an unmistakable imprint on the measured $^{71}$Ga nuclear magnetic resonance (NMR) lineshapes, which we compute using Monte-Carlo simulations and compare with experimental data.

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Arnab Sen, Kedar Damle, Roderich Moessner. 2010-07-26. Fractional spin textures in the frustrated magnet SrCr$_{9p}$Ga$_{12-9p}$O$_{19}$. https://doi.org/10.1103/physrevlett.106.127203

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