Sampling of free-space magnetic pulses

We report free-space detection of magnetic pulses via the Faraday effect wi th shot-noise limited detection. This allows a 10(-8) T / root Hz magnetic field resolution. The orthogonal propagation of the optical probe beam and the THz waves demonstrate a 1.3 ps risetime with a 400 GHz frequency bandwi dth. The temporal and frequency responses of several crystals are reported with a theoretical response function analysis presented. The dispersion of the magnetic pulse into the sensor crystal is illustrated with a theoretica l simulation for comparison. We also contrast the properties of electro-opt ic sampling with this magneto-optic sampling technique.