Nuclear spin coherence properties of¹⁵¹Eu³⁺and¹⁵³Eu³⁺in a Y₂O₃transparent ceramic

We have measured inhomogeneous linewidths and coherence times (T₂) of nuclear spin transitions in a Eu³⁺ :Y₂O₃transparent ceramic by an all-optical spin echo technique. The nuclear spin echo decay curves showed a strong modulation which was attributed to interaction with Y nuclei in the host. The coherence time of the 29 MHz spin transition in¹⁵¹Eu³⁺was 16 ms in a small applied magnetic field. Temperature dependent measurements showed that the coherence time was constant up to 18 K and was limited by spin-lattice relaxation for higher temperatures. Nuclear spin echoes in¹⁵³Eu³⁺gave much weaker signals than for the case of¹⁵¹Eu³⁺ . The spin coherence time for the 73 MHz spin transition in¹⁵³Eu³⁺was estimated to 14 ms in a small magnetic field. The study shows that the spin transitions of ceramic Eu³⁺ :Y₂O₃have coherence properties comparable to the best rare-earth-doped materials available.