  We demonstrate quantum coherent control of a single electron spin in a NV
center in diamond using the Landau-Zener-Stuckelberg interferometry at room
temperature. Interference pattern is observed oscillating as a function of
microwave frequency. The decays in the visibility of the interference are well
explained by numerical simulation which includes the thermal fluctuations of
the nuclear bath which shows that Landau-Zener-Stuckelberg interferometry can
be used for probing electron spin decoherence processes.
