Noise Measurement of Interacting Ferromagnetic Particles with High Resolution Hall Microprobes
Abstract
We present our first experimental determination of the magnetic noise of a superspin‐glass made of <1 pico‐liter<1 pico‐liter frozen ferrofluid. The measurements were performed with a local magnetic field sensor based on Hall microprobes operated with the spinning current technique. The results obtained, though preliminary, qualitatively agree with the theoretical predictions of Fluctuation‐Dissipation theorem (FDT) violation [1].