Magnetostriction in Single-Crystal and Polycrystalline Silver Doped with Rare Earths

We have measured the low-temperature magnetostriction in silver-rare-earth single-crystal and polycrystaline alloys at rare-earth concentrations of about 0.5%. For each monocrystal, the $〈100〉$ and $〈111〉$ magnetostrictions are of the same sign and follow the sign of the Stevens factor $\alpha$. Unannealed polycrystals show quite different behavior from the monocrystals.