The elastic constants of dysprosium and holmium

Abstract

The five single-crystal elastic constants of dysprosium and holmium have been measured within the temperature range 4.2 to 300 K. The large contributions to the elastic constants due to domain and spin rotation effects were eliminated by applying a magnetic field of 2.5 T along the magnetic easy directions. Extrapolation of the temperature dependence in the paramagnetic region to 0 K indicates large magnetic contributions to the elastic constants which have been interpreted as arising from the strain dependence of the exchange energy. Analysis of these contributions permits the evaluation of the first and second derivatives of the nearest and next-nearest exchange interaction parameters. The results are consistent with more limited information obtainable from the anomalous thermal expansion and are consistent with an oscillatory J ( r ).