Coexistence of magnetic and ferroelectric behaviors of pyrochlore Ho2Ti2O7

Rare-earth titanate cubic pyrochlore ${\text{Ho}}_2{\text{Ti}}_2{\text{O}}_7$ ceramics are prepared by the standard solid state reaction. The magnetic, dielectric, and ferroelectric behaviors are measured in order to investigate the multiferroic behaviors of ${\text{Ho}}_2{\text{Ti}}_2{\text{O}}_7$ . Upon the gradual spin ordering sequence with decreasing temperature, a ferroelectric transition with a small polarization is identified. We discuss the origin of ferroelectricity and its possible correlation with the spin order at low temperature.