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The perfect (111)-oriented Co 0.8 Fe 2.2 O 4 thin films are grown on Pt(111)/Si substrate using pulsed laser deposition technique at substrate temperature of 600 °C and laser pulse rate of 5 and 10 Hz. The Fe K -edge X-ray absorption near edge structure analyses revealed that Fe in Co 0.8 Fe 2.2 O 4 films deposited at both 5 and 10 Hz exists in Fe 3 + state leading to the actual composition of Co 0.8 Fe 2.2 O 4 +δ . In order to study the effect of film thickness on the magnetic properties, the film thickness was increased by increase in the pulse rate as well as the time of deposition during pulsed laser deposition process. It was found that by increase of the film thickness, the saturation magnetization and squareness will be generally increased. In the films with same thickness, those which deposited at higher pulse rate have a higher coercivity. In the films deposited at same pulse rate (10 Hz) and different time of deposition, the saturation magnetization, coercivity, and squareness were increased by increasing the thickness, but the coercivity will be decreased with further increasing the thickness due to the relaxation of residual stresses.

An environment friendly, inexpensive solvothermal route is used to synthesize polycrystalline Zn x Sn 1 − x O 2 (0.0 ≤ x ≤ 0.07) nanorods with nanoflower morphology without using any organic solvents, surfactant or any catalytic agent under low hydrothermal pressure. Scanning electron microscopy (SEM) equipped with energy-dispersive x-ray spectra depicts the formation of near stoichiometric Zn x Sn 1 − x O 2 nanorods. SEM analysis reveals that Zn incorporation in SnO 2 decreases the nanorod diameter from ~ 20 nm to ~ 10 nm. High-resolution x-ray diffraction analysis reveals the rutile structure for x ≤ 0.04 samples, while for x = 0.07 a Zn 2 SnO 4 phase is observed. Near edge x-ray absorption fine structure and x-ray photoemission spectroscopy indicate that Zn atoms have been substituted for Sn sites in SnO 2 lattice without forming secondary phases and also create numerous oxygen vacancy in the structure.

A linear polarization selector was made from a three-section sculptured thin film deposited using an oblique angle deposition technique. In this device, the circular Bragg reflector with a left-handed helical structure was sandwiched in between two quarter-wave plates with opposite in-plane birefringence. Within the Bragg regime, the normal incident S-polarized light on this device was reflected, whereas the incident P-polarized light was transmitted through it. The microstructure of the linear polarization selector was also examined by scanning electron microscopy.