The g-factors of discrete levels in nanoparticles

Spin-orbit scattering suppresses Zeeman splitting of individual energy levels in small metal particles. This suppression becomes significant when the spin-orbit scattering rate \tau_{so}^{-1} is comparable with the quantum level spacing \delta. The g-factor exhibits mesoscopic fluctuations; at small \delta\tau_{so} it is distributed according to the Maxwell distribution. At \delta\tau_{so}\to 0 the average g-factor levels off at a small value g\sim(l/L)^{1/2} given by the ratio of the electron mean free path l to the particle size L. On the contrary, in 2D quantum dots the g-factor is strongly enhanced by spin-orbit coupling.Comment: 4 page

Update of the Electron and Muon g-Factors

I give an overview of the different contributions to the electron and muon anomalous magnetic moments in the Standard Model. Special emphasis is given to recent QED results as well as to the hadronic light-by-light scattering contribution to the muon anomaly.Comment: Talk given at the QCD-12 Conference in Montpellie

Isoscalar g Factors of Even-Even and Odd-Odd Nuclei

We consider T=0 states in even-even and odd-odd N=Z nuclei. The g factors that emerge are isoscalar. We find that the single j shell model gives simple expressions for these g factors which for even-even nuclei are suprisingly close to the collective values for K=0 bands. The g factors of many 2+ in even-even nuclei and 1+ and 3+ states in odd-odd nuclei have g factors close to 0.5