Investigations of optical coherence properties in an erbium-doped silicate fiber for quantum state storage

We studied optical coherence properties of the 1.53 μm telecommunication transition in an Er3+-doped silicate optical fiber through spectral holeburning and photon echoes. We find decoherence times of up to 3.8 μs at a magnetic field of 2.2 T and a temperature of 150 mK. A strong magnetic-field dependent optical dephasing was observed and is believed to arise from an interaction between the electronic Er3+ spin and the magnetic moment of tunneling systems in the glass. Furthermore, we observed fine-structure in the Erbium holeburning spectrum originating from superhyperfine interaction with 27Al host nuclei. Our results show that Er3+-doped silicate fibers are promising material candidates for quantum state storage.