Spectroscopic Study of Magnetic Phenomena in DyAsO4and DyVO4

The magnetic properties of DyAs${\mathrm{O}}_4$ and DyV${\mathrm{O}}_4$ have been studied by high-resolution optical spectroscopy. The strength of the nearest-neighbor interaction in DyAs${\mathrm{O}}_4$ has been found from the observed line splittings. The spectral behavior in a magnetic field indicates that DyAs${\mathrm{O}}_4$ has the same magnetic properties previously observed in DyV${\mathrm{O}}_4$. In addition, an unexpected third phase is reported to exist in the transition region. The ordered magnetic structure is also determined from the high-field behavior.