Electric control of collective atomic coherence in an erbium-doped solid

We demonstrate the fast and accurate control of the evolution of collective atomic coherences in an erbium-doped solid using external electric fields. This is achieved by controlling the inhomogeneous broadening of erbium ions emitting at 1536 nm using an electric field gradient, thanks to the linear Stark effect. The manipulation of atomic coherence is characterized with the collective spontaneous emission (optical free induction decay (FID)) emitted by the sample after an optical excitation, which does not require any previous preparation of the atoms. We show that controlled dephasing and rephasing of the atoms by the electric field result in collapses and revivals of the optical FID. Our results show that the use of external electric fields does not introduce any substantial decoherence and enables the manipulation of collective atomic coherence with a very high degree of precision on the timescale of tens of nanoseconds. This provides an interesting resource for photonic quantum state storage and quantum state manipulation.