Dielectric properties of pulsed-laser-deposited calcium titanate thin films

We have deposited CaTiO3 thin films on SrRuO3 electrode layers on SrTiO3 and LaAlO3 substrates by pulsed laser deposition. The low-frequency dielectric properties were measured from 4 to 300 K. We found that the dielectric constants of 1-μm-thick CaTiO3 films are very close to that observed in the bulk materials. The dielectric loss depends on the temperature and is on the order of 10−4 at low temperature. The dielectric constants of the films can be tuned by electric field by 6% at room temperature and 10% at 200 K.