Ion-beam bombardment of solid surfaces with rare gas ions is used extensively in conjunction with XPS and AES for surface cleaning and depth profiling. It is sometimes not appreciated that the process can give rise to extensive chemical changes in the surface to be examined. The purpose of this investigation is to study this ion-induced chemical damage. As a vehicle for this, changes in the elemental chemical states associated with some transition metal oxides have been examined using XPS, when the oxides were subjected to progressive periods of argon ion bombardment. Chemical reduction of all oxides investigated has been observed and the data have been compared with theoretical predictions from a current model for preferential oxygen removal. Measurements of the core electron energy levels in oxides and some hydroxides of iron, cobalt, titanium and niobium have been made and the results are tabulated.

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We demonstrate surface plasmon resonance (SPR) fiber devices based upon ultraviolet inscription of a grating-type structure into both single-layered and multilayered thin films deposited on the flat side of a lapped D-shaped fiber. The single-layered devices were fabricated from germanium, while the multilayered ones comprised layers of germanium, silica, and silver. Some of the devices operated in air with high coupling efficiency in excess of 40 dB and an estimated index sensitivity of Δλ=Δn ¼ 90 nm from 1 to 1.15 index range, while others provided an index sensitivity of Δλ=Δn ¼ 6790 nm for refractive indices from 1.33 to 1.37.

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