Abstract
We exploit the potential of the spin noise spectroscopy (SNS) for studies of nuclear spin dynamicsinn-GaAs. The SNS experiments were performed on bulkn-type GaAs layers embedded into ahigh-finesse microcavity at negative detuning. In our experiments, nuclear spin polarisation ini-tially prepared by optical pumping is monitored in real time via a shift of the peak position in theelectron spin noise spectrum. We demonstrate that this shift is a direct measure of the Overhauserfield acting on the electron spin. The dynamics of nuclear spin is shown to be strongly dependenton the electron concentration.