Abstract

In ZnWO₄ the Cr³⁺ ion is substituted for the relatively large Zn²⁺ site. Therefore, the crystal field strength at the Cr³⁺ site is rather low, and an extreme red shift of the absorption and emission bands occurs. No R lines are observed; i.e., all emission arises from the broadband ⁴T₂-⁴A2 transition. In addition the crystal field splits the ⁴T₂ level because of its low symmetry (symmetry 2, level separation 1.000 cm⁻¹). This yields a further red shift of the emission band with maximum intensity near 1-µm wavelength.

© 1984 Optical Society of America