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1

SHI irradiation induced modifications of plasmonic properties of Ag-TiO2 thin film and study using FDTD simulation

Sharma Himanshu, Singhal R.

Materials Science Poland

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2019

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Vol. 37, No. 3

373--380

EN

Modifications in morphological and plasmonic properties of heavily doped Ag-TiO2 nanocomposite thin films by ion irradiation have been observed. The Ag-TiO2 nanocomposite thin films were synthesized by RF co-sputtering and irradiated by 90 MeV Ni ions with different fluences. The modifications in morphological, structural and plasmonic properties of the nanocomposite thin films caused by ion irradiation were studied by transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-Vis absorption spectroscopy. The thickness of the film and concentration of Ag were assessed by Rutheford backscattering (RBS) as ~50 nm and 56 at.%, respectively. Interestingly, localized surface plasmon resonance (LSPR) appeared at 566 nm in the thin film irradiated at the fluence of 1 × 1013 ions/cm2. This plasmonic behavior can be attributed to the increment in interparticle separation. Increased interparticle separation diminishes the plasmonic coupling between the nanoparticles and the LSPR appears in the visible region. The distribution of Ag nanoparticles obtained from HR-TEM images has been used to simulate absorption spectra and electric field distribution along Ag nanoparticles with the help of FDTD (Finite Difference Time Domain). Further, the ion irradiation results (experimental as well simulated) were compared with the annealed nanocomposite thin film and it was found that optical properties of heavily doped metal in the metal oxide matrix can be more improved by ion irradiation in comparison with thermal annealing.

2

UV-Vis studies of 800 keV Ar ion irradiated NiO thin films

Mallick P., Mishra D. K., Kumar P., Kanjilal D.

Materials Science Poland

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2015

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Vol. 33, No. 3

555--559

EN

We report the evolution of optical absorption properties of 800 keV Ar ion irradiated NiO thin films through UV-Vis characterization. Our results indicate the existence of both Mott-Hubbard (d → d transition) and charge-transfer (p ! d transition) characteristic of NiO. The optical band gap of NiO increases from 3.58 to 3.75 eV when irradiated at the fluence of 5 x 1014 ions cm-2 but it does not show any remarkable variation upon 800 keV Ar ion irradiation at higher fluences. The refractive index and electron polarizability at different ion fluences have been determined from the optical band gap. Both refractive index and electron polarizability follow an opposite trend to that of the energy gap as a function of ion fluence.

3

Atomistic Analysis Of Radiation-Induced Segregation In Ion-Irradiated Stainless Steel 316

Lee G.-G., Jin H.-H., Chang K., Lee B. H., Kwon J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2B

1179--1184

EN

Stainless steel (SS) is a well-known material for the internal parts of nuclear power plants. It is known that these alloys exhibit radiation-induced segregation (RIS) at point defect sinks at moderate temperature, while in service. The RIS behavior of SS can be a potential problem by increasing the susceptibility to irradiation-assisted stress corrosion cracking. In this work, the RIS behavior of solute atoms at sinks in SS 316 irradiated with Fe4+ ions were characterized by atom probe tomography (APT). There were torus-shaped defects along with a depletion of Cr and enrichment of Ni and Si. These clusters are believed to be dislocation loops resulting from irradiation. The segregation of solutes was also observed for various defect shapes. These observations are consistent with other APT results from the literature. The composition of the clusters was analyzed quantitatively almost at the atomic scale. Despite the limitations of the experiments, the APT analysis was well suited for discovering the structure of irradiation defects and performing a quantitative analysis of RIS in irradiated specimens.

4

Impedance of reverse biased diodes irradiated with krypton ions with energy of 250 MeV

Poklonski N. A., Gorbachuk N. I., Ermakova A. V., Tarasik M. I., Shpakovski S. V., Filipenia V. A., Skuratov V. A., Wieck A., Kołtunowicz T. N.

Przegląd Elektrotechniczny

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2012

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R. 88, nr 7a

312-314

EN

The p+n-junction silicon diodes irradiated with krypton ions with the energy of 250 MeV were studied. The distance [delta] between the p�yn-junction boundary and calculated maximum in the distribution of the primary vacancies was about 26.4 žm. It was shown that transformations of a complex plane plot of the electric modulus at the increased reverse bias take place due to a change in the impedance ratio ZL/ZJ of the irradiation damaged layer ZL to space charge region ZJ as well as due to changes in the electron population of the energy levels of irradiation-induced defects.

PL

Przebadano diody krzemowe o typu p+n naświetlane jonami kryptonu o energii 250 MeV. Odległość [delta] między granicą złącza p+n i obliczonym maksimum w rozkładzie wakatów pierwotnych wyniosła około 26,4 žm. Wykazano, że przekształcenia zespolonej płaszczyzny modułu elektrycznego przy zwiększonej polaryzacji zaporowej złącza mogą nastąpić pod wpływem zmiany stosunku impedancji ZL/ZJ warstwy zdefektowanej promieniowaniem ZL do impedancji obszarów z ładunkiem przestrzennym ZJ, jak również ze względu na zmiany w koncentracji elektronów na poziomach energetycznych defektów powstałych poprzez promieniowanie.

5

Formation of nanostructures with a controlled size distribution in Si-based gels by ion irradiation

Pivin J.C.

Materials Science Poland

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2005

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Vol. 23, No. 1

101--109

EN

Studies of irradiation effects in inorganic polymers and gels performed at CSNSM during the past 10 years are overviewed and examples of precipitations with interesting applications (C, Si, metals) occurring during the conversion into ceramics are presented. The precipitation yield, as a function of irradiation fluence or annealing conditions, and particle physical properties were investigated by means of various techniques, depending on their nature. The rates of gel-to-ceramics conversion and of precipitation are determined by the density of electronic excitations produced by ion irradiation (collision cascades slightly assisting the diffusion of metal atoms). Particles formed by ion irradiation show a narrower range of sizes and consequently more interesting characteristics for magnetic or optical applications than those formed in heat-treated gels.

6

The influence of defect structure on the surface sputtering of metals under irradiation of swift heavy ion in the inelastic energy loss region

Cheblukov Y., Didyk A., Hofman A., Semina V., Starosta W.

Nukleonika

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2004

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Vol. 49, nr 1

15-21

EN

The results of the influence of heavy ion irradiation in the inelastic energy loss region on the structure of some metals such as nickel, single crystal tungsten, chromium-nickel stainless steel and cold-deformed gold are presented. It was shown that the sputtering (evaporation) yield strongly depends on the density of defects in these metals. The sputtering yield starts to grow strongly with the increase of damages created by elastic and inelastic energy heavy ion losses. The stainless steel surface structure behaved differently under irradiation than the pure metal surface structure.