Zirconia has attracted very much the attention of technologists and scientists due to its combined electrical

chemical

optical

and mechanical characteristics. Zirconia has prominent characteristics such as chemical stability

high mechan ical strength

high resistance to corrosion

heat resistance

electric insulation

high refractive index

etc

which makes this material suitable for optical application. It has been reported that pure zirconia presents low phonon energy

increasing the probability of radiative transitions in rare-earth doped samples. Interest in nanocrystalline zirconia ceramics with average grain sizes below 100 nm has increased during the past few years as their properties (such as sinterability and superplastic behavior) are often significantly different and considera bly improved compared with conventional zirconia ceramics with coarser grain structures. Synthesis of powder with high purity

ultrafine

agglomerate-free and narrow size distribution is the first and perhaps the most important step in producing nano-zirconia ceramics with desirable microstructure and characterization. Various techniques including wet-chemical synthesis by precipitation of hydroxides from salt have been the most commonly used methods for the synthesis of nano-zirconia powders. In this paper

Zirconia doped with 1% Er

3+

ions was prepa red by solid phase reaction method. The XRD showed that the crystal structure of this material was polygonal. Raman spectrum indicated that its phonon energy waslow. Its emission spectrum under the excitation of the third harmonic of a Nd:YAG laser (355nm) and its up-conversion spectrum with strong green emission and weak red emission under the excitation of a semiconductor diode laser (980nm) we re obtained. The strong green and weak red emission was caused by the low phonon energy and the low doped concentration in the sample.