Infrared optical properties of PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 heterostructures on platinized silicon substrate

PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 heterostructures have been grown on Pt/Ti/SiO2/Si substrates by chemical solution routes. Optical properties of the PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 heterostructures were studied by infrared spectroscopic ellipsometry (IRSE) in the spectral range of 2.5–12.5 μm. The optical constants of PbZr0.4Ti0.6O3 and La0.5Sr0.5CoO3 thin films were determined by fitting the IRSE data using a classical dielectric model and a Drude dielectric model, respectively. For PbZr0.4Ti0.6O3 thin films, the refractive index decreases and the extinction coefficient increases as the wavelength increases. For La0.5Sr0.5CoO3 thin films, the refractive index and the extinction coefficient increase as the wavelength increases. The absorption coefficient of La0.5Sr0.5CoO3 thin films is greater than 104 cm-1 for the wavelength range of 2.5–12.5 μm. The absorption coefficient of PbZr0.4Ti0.6O3 thin films on a La0.5Sr0.5CoO3/Pt/Ti/SiO2/Si substrate is smaller than that on a Pt/Ti/SiO2/Si substrate by a factor of two.