Mesoscopic fluctuations of orbital magnetism in size quantized metals

We evaluate the distribution function of mesoscopic fluctuations of orbital magnetic response in finite-size level-quantized metal particles and Aharonov–Bohm rings for temperatures smaller than the mean level spacing. We find a broad distribution with the reduced moments much larger than the mean. For strong spin–orbit interaction we find very long tails due to thermal activation of large effective moments of the electrons at the Fermi level.