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A series of CdxCo1-xCr0.5Fe1.5O4 ferrite sample with (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) have been prepared by powder metallurgy method. The structural, morphological, magnetic and optical properties of prepared samples have been characterized by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM), Vibrating sample magnetometer (VSM) and UV–visible spectroscopy respectively. The distribution of cation in site-A, site-B and lattice parameters have been deduced by X-ray-diffraction-data analysis. The lattice constant (A°) was found to increase with increment of Cd2+ contents in the spinel ferrites. The hysteresis curves undoubtedly designate the soft nature of the prepared ferrite samples. The saturation magnetization (Ms) decreases with increasing Cd contents3w, this result is interrelated to the magnetic moments of Cd2+ ions. The Y–K angles decrease with addition of cadmium content and this decrement in the Y–K angles proposes the lessening of triangular spin arrangements on octahedral sites which consequently lead to decrease the A-B interaction. The band gap energy is showing the increasing trend which is due to decreasing crystallite size.

The simple and cost-effective powder metallurgy method has been employed to prepare a series of copper substituted cobalt chromium ferrites CuxCo1-xCr0.5Fe2O4 (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0). The calcination of the samples has been carried out at 1100 °C for 24 h. X-Ray Diffractometer (XRD) and Fourier transform infrared spectroscopy (FTIR) measurement proves the formation of cubic spinel ferrites. Vibrating Sample Magnetometer (VSM)) analysis revealed that the substitution of copper in the Co-Cr ferrites leads to reduce the magnetic moment that in turns decrease the saturation magnetization and coercivity. The Ultra violet visible spectroscopy (UV–VIS) showed that the band gap energy increases with copper substitution which is due to reduction in crystallite size. The results indicate that the replacement of copper with the cobalt-chromium ferries strongly influences the crystal structure, microstructure, magnetic parameters and band gap energy.

A series of Ti 0.9 Fe 0.1-x Ni x O 2 (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) has been synthesized through the solid state reaction method at annealing temperature of 1100 °C for two hours. The synthesized samples have been analyzed by X-Ray diffractometer (XRD), Raman spectroscopy, Scanning electron microscopy (SEM), Energy dispersive X-ray spectroscopy (EDX), Vibrating sample magnetometer (VSM) and ultraviolet visible (UV–VIS) spectroscopy for structural investigations, defects measurements, surface morphology, magnetic and optical properties respectively. Structural analysis has revealed the dominant structure of rutile. An intensity loss and peak broadening of TiO 2 (rutile) vibration lines have been observed from Raman analysis, which is an indication of presence of oxygen vacancies. Magnetic analysis has revealed ferromagnetic behavior at room temperature. Optical characterization has shown the blue shift in band gap energy with increase of Ni concentration.

Thin films of Zn0.9 Co0.1−xNixO (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) series were deposited by Pulsed Laser deposition technique (PLD) on a single crystal (100) silicon substrate. The structure of the films was confirmed as single phase hexagonal wurtzite structure by X-ray diffraction technique (XRD). The highest intensity peak was found at (002) plane. The surface morphology of thin films studied by Scanning Electron Microscope (SEM) depicted the high grain growth with definite boundaries. The room temperature resistivity measurements were carried out by four-point Probe methods which showed the semiconducting behavior of the thin films. Magnetic properties characterized by Vibrating Sample Magnetometer (VSM) at room temperature, exhibited the weak ferromagnetic or superparamagnetic behavior due to the alignment of the spins in the same direction around the oxygen vacancy and Co/Ni ions. Optical properties were observed by Spectroscopic Ellipsometry. The thickness of the films lied in 200–265 nm range and the bandgap energy was found to decrease from 3.09 to 3.03 eV confirming the inclusion of Ni a deep level impurity.

In this research work a series of Ti0.9Fe0.1-xNixO2 thin films with Ni concentration varying from x=0 to 0.1 have been grown onto single crystal Si (100) substrate by pulsed laser deposition. The two ferromagnetic impurities Fe and Ni were co-doped in TiO2 films simultaneously in order to enhance their optical, magnetic and electrical properties. The targets for the deposition of thin films have been prepared via solid state reaction route. The thin film samples were annealed in air at 800°C for two hours in order to control their phase stability, carrier concentration and magnetic properties. Their structural properties were studied by X-ray diffractometer, which revealed rutile phase of TiO2. The film surface morphology, observed by scanning electron microscopy, was porous and smooth with the structure of rutile phase. The magnetic properties were investigated by vibrating sample magnetometry at room temperature and showed a ferromagnetic behavior for all the thin films. The optical properties, investigated by spectroscopic ellipsometry revealed a red shift in band gap energy as a function of Ni contents. Electrical characterization has been done by four probe Hall effect measurements at room temperature. The N-type semiconducting behavior has been observed at x=0, 0.02, 0.04 and 0.06 and p-type behavior for x=0.08 and 0.1. P-type conductivity is required for use in spintronics devices.

Laser induced breakdown spectroscopy of ZrO2 plasma in the presence and absence of magnetic field has been investigated. The plasma was generated by employing Nd: YAG laser (1064 nm, 10 ns) at various fluences ranging from 6.4 J cm−2 to 25.6 J cm−2 under argon environment of pressure of 100 Torr. Both emission intensity and electron temperature show increasing trend with increasing the fluence, whereas, electron number density of ZrO2 plasma decreases with increasing the laser fluence. It is revealed that values of emission intensity, electron temperature and electron number density of ZrO2 plasma are slightly higher in the presence of magnetic field as compared to field free case at all fluences. This increase in plasma parameters is attributed to magnetic confinement and Joule heating effect. With the variation of fluence the electron temperature of ZrO2 plasma varies slightly from 5345 K to 5475 K in the absence of magnetic field, whereas in case of magnetic field this value enhances from 5435 K to 5600 K. Similarly the electron number density of ZrO2 plasma varies from 1.80 × 1018 cm−3 to 3.50 × 1018 cm−3 in the absence of magnetic field, whereas in case of magnetic field, the variation in electron number density varies from 1.75 × 1018 cm−3 to 4.25 × 1018 cm−3. The existence of magnetic confinement effects is confirmed by the analytical evaluation of plasma parameter β, which is smaller than 1 under all experimental conditions. It is also revealed that both the laser fluence as well as magnetic field significantly influence the ZrO2 plasma parameters.

This paper reports the fabrication and characterization of silicate glass-ceramics doped with (0-12mol%) CaF2. TGA-DSC analysis was carried out to determine the crystallization temperature and stability of glass measured by two glass parameters; Hruby parameter KH=(Tx-Tg)/(TL-Tx) and Weinberg parameter KW=(Tc-Tg)/TL. It was found that with CaF2 doping improved sinterability at low temperature and provided stability to the glass. The XRD pattern exhibits a single phase of combeite and doping of CaF2 cause increase in crystallite size. Microstructure of samples was also improved with CaF2 addition, pores were significantly reduced. After 15days immersion in simulated body fluid all samples developed apatite layer onto its surface. Hence, the addition of CaF2 provided bioactive glass-ceramic material having a low processing temperature.

This paper is dedicated to investigate the effect of Co 2+ ions in magnetite Fe 3 O 4 nano-particles with stoichiometric formula Co x Fe 3-x O 4 where (x = 0, 0.05, 0.1 and 0.15) prepared by co-precipitation method. The structural, thermal, morphological, magnetic and optical properties of magnetite and Co 2+ doped magnetite nanoparticles have been carried out using X-ray Diffractometer, Fourier Transform Infrared Spectroscopy, Themogravimetric Analysis, Scanning Electron Microscopy, Vibrating Sample Magnetometer (VSM) and UV–Vis Spectrometer (UV–Vis) respectively. Structural analysis verified the formation of single phase inverse spinel cubic structure with decrease in lattice parameters due to increase in cobalt content. FTIR analysis confirms the single phase of Co x Fe 3-x O 4 nanoparticles with the major band at 887 cm −1 , which might be due to the stretching vibrations of metal-oxide bond. The DSC results corroborate the finding of an increase in the maghemite to hematite phase transition temperature with increase in Co 2+ content. The decrease in enthalpy with increase in Co 2+ concentration attributed to the fact that the degree of conversion from maghemite to hematite decrease which shows that the stability increases with increasing Co 2+ content in B-site of Fe 3 O 4 structure. SEM analysis demonstrated the formation of spherical shaped nanoparticles with least agglomeration. The magnetic measurements enlighten that the coercivity and anisotropy of Co x Fe 3-x O 4 nanoparticles are significantly increased. From UV–Vis analysis it is revealed that band gap energy increases with decreasing particle size. This result has a great interest for magnetic fluid hyperthermia application (MPH).

This current project is dedicated to a fast, easy and one step method for the synthesis of gold nano-particles. Gold (Au) nano-particles have been fabricated by laser ablation method in de-ionized water. The purpose was to explore the dependence of the various properties of the gold nano particles on the nature of laser. In order to prepare colloidal solutions, a low power continuous wave (CW) diode laser and a nanosecond pulsed Nd:YAG laser have been used to ablate the gold target. The structural, physical, optical and thermal characteristics of prepared nano-particles have been investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), UV–vis spectroscopy and thermal conductivity of liquids and gases unit (TCLGU), respectively. The XRD analyses revealed the formation of polycrystalline gold nano-particles with (111), (200) and (220) plans in case of both the lasers. AFM micrographs showed that prepared nano-particles are spherical in dimensions. The size of nanoparticles synthesized by CW laser ranges from 5 to 20 nm whereas the size ranges from 12 to 49 nm in case of pulsed laser. UV–vis spectroscopy showed surface plasmon resonance (SPR) peak at 512 nm for CW laser prepared nanoparticles as compared to pulsed laser at 525 nm which is also indicative of the smaller size in case of CW laser. The thermal conductivity of colloidal solution prepared by CW laser is 33% whereas in case of pulsed laser is 48% more as compared to the deionized water (base liquid).

The series of M-type Ba1-xSrxFe12O19 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1) have been fabricated using powder metallurgy route. The effects of strontium ions have been systematically investigated. The samples are sintered at 1200 °C for 2 h. The structural properties and surface morphology is determined using X-ray diffraction technique, Fourier Infrared Spectroscopy and Field Emission Scanning Electron Microscope respectively. The magnetic and optical properties are carried out using vibrating sample magnetometer and UV–vis spectroscopy. The XRD analysis revealed that these samples have hexagonal structure. FTIR analysis confirmed that bands in the range 430–590 cm−1 are due to the stretching vibration of oxygen atom and metal ions (M-O) that is Fe-O confirming the formation of hexa-ferrite. The average grain size is determined using FSEM i.e about 0.37–1.5 μm. The VSM analysis showed that saturation magnetization decreased with increasing concentration of Sr+2 ions and this decrease is due to the different site occupation of Sr+2 and Fe+3 ions. The band gap energy decreased with the increasing concentration of strontium ions. This is due to the vacancies of electrons in the valance band of Ba and Sr. The decrease in the distance between conduction and valance band causes the increase in conductivity due to which band gap energy decreases. The widest applications of these hard ferrites permanent magnets are in motors, speakers sensors and MRI systems.

Nanostructured thin films of carbon were synthesized and investigated for their electrical, optical, structural and surface properties. Pulsed Laser Deposition (PLD) technique was used for the preparation of these films under Argon gas environment. A KrF Laser (λ=248 nm) was used as source of ablation and plasma formation. It was observed that the carbon ions and the background gas environment has deep impact on the morphology as well as on the microstructure of the films. Time of Flight (TOF) method was used to determine the energies of the ablated carbon ions. The morphology of film surfaces deposited at various argon pressure was analysed using an atomic force microscope. The Raman spectroscopic measurement reveal that there is shift in phase from sp3 to sp2 and a decrease in FWHM of G band, which is a clear indication of enhanced graphitic clusters. The electrical resistivity was also reduced from 85.3×10−1 to 2.57×10−1 Ω-cm. There is an exponential decrease in band gap Eg of the deposited films from 1.99 to 1.37 eV as a function of argon gas pressure.

Co and Ni codoped ZnO-based dilute magnetic semiconductors having a general formula of Zn0.9Co0.1−xNixO (x = 0.0, 0.02, 0.04, 0.06, 0.08 and 0.10) have been prepared using a simple solid-state reaction method. A single-phase hexagonal wurtzite structure, confirmed by X-ray diffraction, has been developed for Zn0.9Co0.1−xNixO (x

Crystals of zinc-antimony oxide are synthesized by Solid state synthesis technique. Fine crystals of zinc-antimony oxide are formed by heating the sample at 900 °C for one hour. Crystals are investigated using single crystal X-ray diffraction and found that the compound crystallizes in the tetragonal crystal system with a space group-135, P 42/m b c, indicating primitive tetragonal crystal structure. Crystal structure refinement and ORTEP representation of the zinc-antimony oxide shows two distinct crystallographic oxygen atoms represented by O1 and O 2 ·FTIR spectrum also describe Zn O and Sb O bonds formation and improvement in optical absorption properties.

A series of antimony substituted cobalt ferrites (CoSb 0.3 Fe 1.7 O 4 ) thin films have been deposited employing Electron Beam Deposition technique. The as deposited thin films have been post annealed at different temperature such as 200, 300, 400 and 500 °C. The structural, surface, magnetic and optical properties of as-deposited and post annealed thin films have been studied using X-ray diffractometer, Raman spectroscopy, and Atomic Force Microscope, Vibrating Sample Magnetometer, spectroscopy ellipsometry and UV–vis techniques respectively. The X-ray diffraction and Raman spectroscopy analysis have confirmed the growth of single phase cubic spinel structure in thin films after post annealing. It is observed that the roughness of the thin films decreases and magnetization increases as the annealing temperature increases but not exceeded to as-deposited film. As the post annealing temperature increases the band gap energy increases which shows that the density of defects decreases and structure turn towards crystalline state from amorphous.

Nano crystalline CdS thin films have been deposited on glass substrate employing chemical bath deposition technique by varying thiourea concentration in two different cadmium sources as cadmium chloride (S 1 ) and cadmium acetate (S 2 ). The aim of this research is to investigate the effect of thiourea concentration on optical and structural properties of the deposited CdS thin films. XRD analysis reveals that the CdS thin films fabricated by using S 1 have zinc blende cubic structure and S 2 have hexagonal as well as cubic structure. UV–vis studies demonstrate that as the thiourea concentration increases transmission spectra shift towards the shorter wavelength and optical band gap of CdS thin films also increases from 2.45 to 2.71 eV in S 1 and 2.65–2.74 eV in S 2 . In absorption spectra, a blue shift in the band gap was observed which indicates the formation of CdS nanoparticles measured as 31–9.91 nm in S 1 and 30–15.02 nm in S 2 .

The main objective of the study was to control the degradation rate of material at a higher degradation rate improving the chemical stability of the material. Ta is known to have good chemical resistance, biocompatibility and show no adverse biological response. In the present study, SiO 2 –Na 2 O–CaO–P 2 O 5 bioceramics with different Ta 2 O 5 contents was prepared by solid state sintering method at 1000 °C. The as-sintered ceramics were subjected to immersion studies in stimulated body fluid (SBF) for 21 days under static condition and characterized by XRD, FTIR, SEM, and AAS. The findings of the research indicate that the addition of Ta 2 O 5 controlled degradability, and all samples showed sufficient bioactivity.

The thin films of Ti0.9F0.1-xCrxO2 (x = 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) have been deposited on Si (100) substrate by pulsed laser deposition (PLD) technique at substrate temperature of 630ᶱC. The deposition time was 60 min. The synthesized samples have been characterized by X-Ray diffractometer (XRD) for structural study, Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) for surface analysis, EDX for elemental composition, Vibrating sample magnetometer (VSM) for magnetic properties, Spectroscopic ellipsometry (SE) for optical properties and four probe Hall effect measurements for electrical properties. Structural analysis revealed pure phase of rutile without any secondary peak. AFM and SEM measurements revealed decrease in crystallinity and increase in grain size. Magnetic characterization showed ferromagnetic behavior for all thin films at room temperature. Optical characterization revealed red shift in band gap energy with increasing amount of Cr concentration. Semiconducting behavior with n- type carriers is observed from electrical measurements.

A bioactive ceramic in (48− x ) SiO 2 –36CaO–4P 2 O 5 –12Na 2 O– x TiO 2 (where x = 0, 3.5, 7, 10.5 and 14 mol%) system was prepared by solid state sintering method. The in vitro bioactive properties of bodies were evaluated using stimulated body fluid under static condition at 37 °C. The formation of hydroxyl-carbonated apatite layer on the surface of samples was examined by XRD, FTIR, SEM and AAS. It was found that partial substitution of SiO 2 with TiO 2 produced a positive impact on the bioactivity of the specimens. Addition of TiO 2 ≤10.5 mol% to the system not only enhanced the bioactive properties but also accelerates the apatite forming process.

Antimony doped cobalt ferrite with general formula CoSbxFe(2-x)O4 (with x=0.0, 0.1, 0.2, 0.3, 0.4, 0.5) have been synthesized by powder metallurgy method. The structural, chemical, microstructural, magnetic and optical properties have been investigated using XRD diffractometer, Fourier Transform Infra-red Spectroscopy, Scanning Electron Microscope (SEM), Vibrating Sample Magnetometer (VSM) and UV-Visible Spectrometer respectively. XRD micrographs of all the samples have been confirmed the formation of spinel structure having major peaks at (220), (311), (400), (422), (511), (440). The increase in lattice parameter is due to the replacement of smaller cation Fe+3 by larger cation Sb+3. FTIR analysis shows major bond (M-O) vibrational bond confirms the spinel structure. When the concentration of antimony is zero then the value of saturation magnetization is 45.5emu/gm. But there is a sharp increase in Ms at x=0.1, this is due to the doping of Sb. The Co+3 and Sb+3 ions prefer to occupy the site B. After that there is decrease in Ms from x=0.2-0.4 this is may be due to the possible concentration of Sb+3 to the site A as compared to octahedral site. The band gap energy decreases as the antimony concentration increases which is associated with the decrease in grain size.

Three samples of dilute magnetic semiconductors (DMS) have been prepared by solid state reaction method at sintering temperature of 950 °C for 5 hours. Their structural, optical, electrical and magnetic properties are optimized by X-Ray Difractometer (XRD), UV-Visible spectrophotometer (UV-Vis), Four point probe method and Vibrating sample magnetometer (VSM) measurements respectively. Surface morphology has been studied by using scanning electron microscope (SEM). Structural analysis showed that a single phase Rutile structure has been attained while Optical and resistivity measurements confirmed their semiconducting behaviors. Magnetic measurements showed weak Ferromagnetic and Paramagnetic behaviors at room temperature.

Samples of composition Zn 0.9 Co 0.1 O, Zn 0.9 Ni 0.1 O, Zn 0.9 Co 0.06 Ni 0.04 O were prepared by powder metallurgy method. Structural property was studied by X-ray diffractometer (XRD), and Fourier transform infrared spectroscopy (FTIR). Magnetic, electrical and optical properties were studied by vibrating sample magnetometer (VSM), four point probe method and UV-Visible spectrophotometer, respectively. Single phase wurtize structure was obtained for Zn 0.9 Co 0.1 O and Zn 0.9 Co 0.06 Ni 0.04 O, while a secondary phase of NiO was found in Zn 0.9 Ni 0.1 O. The bandgap energy found in all samples was less than pure ZnO. Scanning electron microscope (SEM) studied surface Morphology. Moreover, room temperature ferromagnetism (RTFM) was observed for all samples.

The current project deals with the synthesis and characterization of bismuth doped cobalt ferrite with general formula of CoBi x Fe (2-x) O 4 (where x varies from zero to 0.5 with the step size of 0.1). This series have been prepared using powder metallurgy route. The structural, chemical, morphological, elemental, magnetic and optical properties have been investigated using XRD, FTIR, SEM, EDX, VSM and UV Visible spectrometer respectively. Structural measurements show the confirmation of spinel structure. This also shows the decrease in lattice parameters and crystallite sizes, which are due to the replacement of larger cations Fe +3 by smaller cations Bi +3 . Functional groups or characteristic bonds of spinel ferrites have been investigated by FTIR spectrum. SEM micro graphs revealed the spherical shape of the particles, also shows the un-even or non-uniform grain boundaries. An EDX spectrum confirms the elemental composition of the prepared ferrites. UV-Visible spectrometer revealed the increase in band gap with the decrease in grain size. VSM reveals that saturation magnetization decreases with the increase of bismuth oxide content in CoBi x Fe (2-x) O 4 .

The series of Zn0.5Cu0.5-xCox (where x= 0, 0.1, 0.2, 0.3, 0.4, 0.5) dilute magnetic semiconductors have been synthesized using double sintering route. The structural, microstructural, magnetic and optical properties have been carries out using XRD, SEM, VSM and UV-Visible spectroscopy respectively. The XRD analysis has confirmed that Cu and Co ions incorporated in ZnO lattice and replaces ZnO sites without changing wurzite structure. SEM micrographs have showed the clear hexagonal wurzite grains growth. It has been observed that magnetization of all samples reduces as concentration of Cu increases. The ferromagnetism in Cu and Co doped ZnO DMS is due to the secondary phases which is confirmed from XRD pattern there are some secondary phases of CuO, Cu2O in wurzite structure. Ferromagnetism in the DMS was due to the presence of free carriers (holes and electrons) from valance band and localized d-spins of transition metal ions. The Band gap energy decreases as the concentration of Cu increases, which shows that Cu ions have incorporated successfully in ZnO lattice sites.

In the present work a series of six samples of Zn substituted Co-ferrites with general formula Co1-xZnxFe2O4 where (x= 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0) were prepared by standard solid state reaction method. Structure, surface morphology, magnetic and dielectric properties were determined by XRD, FTIR, SEM, VSM, and LCR-meter respectively. Single phase spinel structure was confirmed by XRD. The parameters extracted from XRD revealed an increasing trend of lattice constant and X-Ray density as Zn concentration increases because atomic radius of Zn is greater than that of Co. FTIR spectra show two absorption bands in the wave number range from 500 to 1000 cm-1 which is a typical characteristic of ferrites. Uniform and well-defined particle size was observed in SEM micrographs. MH loops showed that the value of saturation magnetization (Ms) first increases up to x=0.4 (having maximum value) and then decreases because of increasing concentration of non-magnetic Zn ions. Dielectric parameters of all the samples such as tangent loss, dielectric constant were also obtained.

Dilute magnetic oxide materials of composition Zn0.9Co0.1O, Zn0.9Cd0.1O and Zn0.9Co0.06 Cd0.04O were synthesized by Powder Metallurgy Method. Electrical, optical and magnetic properties were studied by Four Point Probe method UV- Visible Spectrophotometer, and Vibrating Sample Magnetometer (VSM) respectively. While, structural property was studied by X-ray diffraction (XRD), and Raman Spectroscopy. Single phase wurtize structure was found for Zn0.9Co0.1O, and Zn0.9Co0.06 Cd0.04O, but a secondary phase of CdO was obtained for Zn0.9Cd0.1O. UV-Vis spectroscopic results confirm the incorporation of the dopants in to the ZnO lattice structure as the band gap energy exhibited red shift. Room Temperature ferromagnetism (RTFM) was found for all the three samples.

NiCu ferrites with the general formula Ni 1-x Cu x Fe 2 O 4 , where x=0, 0.2, 0.4, 0.6, 0.8 have been synthesized by double sintering method. The single- phase spinel structure is confirmed by X-ray Diffractometer. This analysis showed the increasing behavior of lattice parameter due to the larger ionic radii of the Cu ion. Fourier transform infrared spectra confirmed the two prominent bands of spinel ferrites in the range (1000-400) cm -1 . Magnetic properties are studied using Vibrating Sample Magnetometer. It is investigated that the saturation magnetization decreases linearly as the copper concentration increases. The surface morphology is carried out using Scanning Electron Microscopy. The dielectric properties have been investigated as a function of frequency. The dielectric constant is decreased and AC conductivity is increased at higher frequency.

BaFe 12 O 19 thin films have been deposited on p-type Si (1 0 0) substrate employing pulsed laser deposition technique. The films have been deposited under the magnetic field of 0.15, 0.3, 0.45 and 0.6 T applied transverse to the plume, keeping the substrate temperature constant at 300 °C. The aim is to investigate the effect of external magnetic fields on the structural, magnetic, morphological and optical properties of the deposited thin films. A perpendicular uniaxial magnetic anisotropy is observed for the films deposited under B = 0.15 to 0.6 T. The estimated value of anisotropy field has increased with the increase in the applied field. The film deposited under 0.6 T, also exhibited perpendicular anisotropy. The perpendicular loop saturation magnetization increases from 168 to 227.5 × 10 3 A/m as the external field is increased from B = 0.15 to 0.6 T, respectively. The coercivity of in-plane measurements increases with the increase in the magnetic field. The films have grains of the order of few tens of nano meters on the surface. The thickness and band gap energy of the thin films increases monotonically as the applied field during deposition is increased. The maximum values of thickness and band gap energy achieved under 0.6 T, are 128 nm and 2.98 eV, respectively.

The objective of this project is to explore the effect of X-ray irradiation of thin polymeric films deposited at various substrate temperatures. pulsed laser deposition (PLD) technique is used for the deposition of PMMA thin films on glass substrate at 300 °C and 500 °C. These films have been irradiated with various X-rays fluences ranging from 2.56 to 5.76 mJ cm−2. Characterization of the films (before and after the irradiation) is done with help of X-ray Diffractrometer, Optical Microscope, Vickers hardness tester and UV–vis spectroscopy techniques. From XRD data, it is revealed that ordered packing has been improved for the films deposited at 300 °C. However after irradiation the films exhibited the amorphous behavior regardless of the X-ray fluence. Film deposited at 500 °C shows amorphous structure before and after irradiation. Hardness and particle size of thin film have also increased with the increasing substrate temperature. However, the irradiation has reverse effect i.e. the particle size as well as the hardness has reduced. Irradiation has also enhanced the absorption in the UV–visible region.

In this paper we present the effect of low substrate temperature on structural, morphological, magnetic and optical properties of Ba-hexaferrite thin films. Films were deposited on single crystal Silicon (1 0 0) substrate employing the Pulsed Laser Deposition (PLD) technique. The structural, morphological, magnetic and optical properties are found to be strongly dependent on substrate temperature. The low substrate temperatures (room temperature to 200 °C) restrict the formation of larger grains. For the higher substrate temperature i.e., 400 °C, the grain size of the deposited thin film are much larger. The film grown at low substrate temperature do not show any anisotropy. As the substrate temperature is increased, the easy axis of the films alinged itself in the direction parallel to the film plane whereas the hard axis remained in the perpendicular direction. The higher substrate temperature caused the uniaxial magnetic anisotropy, which is very important in magnetic recording devices. The saturation magnetization and optical band gap energy values of 62 emu/cc and 1.75 eV, respectively, were achieved for the film of thickness 500 nm deposited at 400 °C. Higher values of coercivity, squareness and films thickness are associated with the growth of larger grains at higher substrate temperature.

Nickel Cadmium Aluminum Ferrites with the general formula Ni 1− x Cd x Al 0.6 Fe 1.4 O 4 where x =0, 0.25, 0.50 and 0.75 were prepared through standard double sintering reaction method. The crystallography, surface morphology and magnetic properties were studied by X-ray diffractometer (XRD), Scanning Electron Microscope (SEM) and Vibrating Sample Magnetometer (VSM), respectively. The expected single phase spinel structure was confirmed by XRD analysis. Lattice parameter and X-ray density were increased monotonically by increasing Cd concentration due to the larger ionic radii of the cadmium ion. Surface topography of the samples consists of fine cubical shape microstructures. The average grain size increased with increase in cadmium concentration. The saturation magnetization was found to be increased with increase in cadmium content up to x =0.50 and then decreased with further increasing cadmium concentration for x =0.75.

Zn 0.2 Mn 0.81 Zr 0.01 Fe 1.98 O 4 and Zn 0.2 Mn 0.83 Zr 0.03 Fe 1.94 O 4 thin films with different concentrations of Mn and Zr have been deposited on single crystal n-Si (400) at room temperature (RT) by pulse laser deposition technique (PLD). The films have been deposited under two conditions: (i) with the applied external magnetic field across the propagation of the plume (ii) without applied external magnetic field ( B =0). XRD results show the films have spinel cubic structure when deposited in the presence of magnetic field. SEM and AFM observations clearly show the effect of external applied magnetic field on the growth of films in terms of small particle size, improved uniformity and lower r.m.s. roughness. Thin films deposited under the influence of external magnetic field exhibit higher magnetization as measured by the VSM. The optical band gap energy E g , refractive index n, reflection, absorption and the thickness of the thin films were measured by spectroscopy ellipsometer. The reflection of Zn 0.2 Mn 0.83 Zr 0.03 Fe 1.94 O 4 thin films is higher than Zn 0.2 Mn 0.81 Zr 0.01 Fe 1.98 O 4 thin films due to the greater concentration of Zr. The thicknesses of the thin films under the influence of external magnetic field are larger than the films grown without field for both samples. The optical band gap energy E g decreases with increasing film thickness. The films with external magnetic field are found highly absorbing in nature due to the larger film thickness.

The objective of this work is to study the influence of deposition temperature on structural, surface, optical and magnetic properties of the Al doped CdO thin films prepared by pulsed laser deposition (PLD) technique. KrF excimer laser (λ = 248 nm, τl = 20 ns, ν = 10 Hz, ϕl = 2.5 J/cm2) was employed for the deposition of thin films. It is observed by XRD results that films grown at room temperature and 100 °C show preferential growth along (1 1 1) and (2 0 0) directions while high temperatures (200–400 °C) lead to preferential growth along the (2 0 0) direction only. The optical constants (n, k, α, and optical band gap energy) of films measured by spectroscopic ellipsometry show strong dependence upon deposition temperature. M–H loop of films, measured by vibrating sample magnetometer, deposited at 25 °C and 100 °C show paramagnetic nature while films deposited at temperatures (200–400 °C) exhibit ferromagnetic character. Scanning electron micrographs show degraded elongated grains at lower deposition temperatures, while smooth and compact surface is observed for films deposited at higher deposition temperatures.

The structure and surface morphology of Ni-incorporated diamond like carbon (Ni:DLC) films have been investigated. These films were deposited on Si substrates using pulsed laser deposition (PLD) technique. A KrF Excimer laser ( λ = 248 nm) was used for co-ablation from multi component Ni–graphite target. The concentration of Ni was varied by ablating the Ni part of the target with various numbers of laser pulses. The SEM and AFM analysis reveals that the surface is composed of segregates of Ni which increases with the increase in Ni content during the growth process. The structural investigations by XRD and Raman spectroscopy provided information about the orientation of the incorporated constituent and the ordering of the carbon species. Maximum height of the nano structures which were observed on the surface was ∼50 nm. The G-peak of the graphite was shifted towards higher wave number due to enhancement in SP 2 sites which have been increased due to the increase in the Ni concentration. A small change in the surface roughness ranging from 7.78 nm to 13.1 nm due to increased Ni concentration was also observed.

Structural and morphological investigations on optimized nano-structured gold thin film (under vacuum ∼10 −3 Torr) are reported. The Au optimized thin film was deposited on 4 N polished and analytic grade p-type single crystal (111) Silicon wafer by pulsed laser deposition (PLD) technique, under a vacuum of about 10 −3 Torr at room temperature. The space resolved dynamics of the plume is studied by analyzing CCD images of plume. Average size of deposited nanoparticles is along the preferred (111) orientation is ∼ 20 nm using PLD technique. The deposited film is non-uniform with particle size within the range of 6.19 nm–19.62 nm. There is decrease in the value of dislocation line density. XRD and SEM investigations support each other.

Rare earth and transition metal doped (NdFeCo) thin films were fabricated on Si (100) substrate by pulsed laser deposition technique keeping the substrate at constant temperature of 300 °C. A KrF Excimer laser (248 nm, 20 ns) was used as an energy source for the deposition. Thin films were deposited without and under the influence of transverse magnetic field applied across the plume. The applied magnetic field was varied from 3 to 6 kOe. The deposited films were characterized by XRD, FESEM, VSM and SE (Spectroscopic Ellipsometry). The deposited films were amorphous in nature. All the films regardless of the applied magnetic field exhibit perpendicular magnetic anisotropy. The thickness of the thin films was found to increase monotonically from 166 to 266 nm with the increase in the applied external magnetic field. The saturation magnetization has a maximum value of 1682 emu/cc for the film deposited under 4.5 kOe magnetic field. The value of optical band gap energy for the same film is found to have a maximum value of 3.1 eV. The values of both the saturation magnetization and the band gap energy were decreased with the increase in the applied magnetic field.

The contribution of an external magnetic field on the deposition of BaFe12O19 thin film was investigated. For this purpose, two (one with applied field and another without field) thin films of BaFe12O19 were deposited on the C-plane oriented sapphire (Al2O3) substrate employing pulsed laser deposition technique. Crystallographic orientation and texture were determined using an X-ray diffractometer. The magnetic parameters were deduced from a vibrating sample magnetometer (VSM). A spectrometer was used to study the optical properties of the films. The structural results reveal the film to be predominantly single phase with C-plane orientation in both the cases. The film deposited with field, however, has bigger grain size and more perfection in crystallinity. The magnetic parameters show that the film deposited with the field has more remanence magnetization and higher coercive field. The diffuse reflectance of the film deposited with field is much higher due to the increased grain size and roughness.