Terahertz Dielectric Response of Ferroelectric BaxSr1-xTiO3 Thin Films

Terahertz time-domain spectroscopy has been used to investigate the dielectric properties of ferroelectric thin BaxSr1-xTiO3 films in the frequency range of 0.3 to 2.5 THz. The BaxSr1-xTiO3 films were deposited on (001) MgO substrate by pulsed laser deposition. The measured complex dielectric function was compared with the Cole-Cole relaxation model and agreed well with the theoretical fit.