Probing spin dynamics by conductance fluctuations and noise in mesoscopic spin-glass

Millikelvin magnetoconductance studies performed in mesoscopic spin-glass n+-Cd1−xMnxTe wires reveal strong effects of Mn spins upon universal conductance fluctuations. In particular, scattering potential of the frozen spins leads to magnetic and thermal irreversibilities of the fluctuation patterns. Slowly fluctuating spins, on the other hand, are an efficient source of conductance noise providing a real-time probe of spin dynamics.