Broadband dielectric spectroscopy of Ruddlesden–Popper Srn+1TinO3n+1 (n=1,2,3) thin films

We explore the frequency-dependent relative permittivity of Ruddlesden–Popper series Srn+1TinO3n+1 (n=1,2,3) thin films as a function of temperature and dc electric field. Interdigitated capacitors and coplanar waveguides were used to extract the frequency response from 500 Hz to 40 GHz. At room temperature, the in-plane relative permittivities (ϵ11) obtained for Srn+1TinO3n+1 (n=1,2,3) were 42±3, 54±3, and 77±2, respectively, and were independent of frequency. At low temperatures, ϵ11 increases and electric field tunability develops in Sr4Ti3O10.