NMR relaxation in spin ice due to diffusing emergent monopoles I
نویسنده
چکیده
At low temperatures, spin dynamics in ideal spin ice is due mainly to dilute, thermally excited magnetic monopole excitations. I consider how these will affect the dynamics of a nuclear spin (the same theory applies to muon spin resonance if implanted muons do not diffuse). Up to the time scale for nearby monopoles to be rearranged, a stretched-exponential form of the relaxation functions is expected. I work out the expected exponent in that exponential and the formulas for the T1 (longitudinal) and T2 (dephasing) relaxations, as a function of the monopole density (and implicitly the temperature).
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تاریخ انتشار 2012