Effect of isotopic purification on spectral-hole narrowing in 167Er3+ hyperfine transitions

We investigated spectral-hole narrowing in optical transitions between hyperfine sublevels in isotopically purified erbium ions (Er-167(3+)). The homogeneous broadening Gamma(h) of the optical transition was measured in purified and non-purified Er3+-doped crystals via spectral-hole burning. The measured Gamma(h) in the purified Er-167(3+) exhibited a significant reduction of the hole width because the fluctuation of the local magnetic field induced by the electron spins of the surrounding Er3+ ions was eliminated. Because the narrowing of the Gamma(h) is equivalent to the prolongation of the coherence time, the isotopic purification is effective for the coherent manipulation of quantum states. (C) 2017 The Japan Society of Applied Physics