For the first time to the authors' knowledge, efficient control of the position of a macro object by coherent light was demonstrated. The minimal controllable mechanical displacement induced by the light pressure was 9 pm. No dependence of light pressure on wavelength in a broad wavelength range (405-1560 nm) was observed, as predicted by Maxwell's theory.

The sensitivity of an integrated optical sensing device can be enhanced by coating it with a high refractive index layer, while both incoupled intensity and spatial resolution are maintained. The potential for enhanced sensing is demonstrated using titanium indiffused waveguiding structures in LiNbO(3) coated with a TiO(2) film. To the best of our knowledge, it could be measured for the first time that the outcoupled intensity at the surface was enhanced by a factor of 12-15 while keeping the penetration depth of the evanescent field constant of the order of only a few tens of nanometers. The evanescent fields of the guided modes were measured and characterized with a scanning near-field optical microscope and are in accordance with the numerical simulations.

Static probes, although widely used in supersonic tunnels and in flight, have not formed the basis for many reports on their design and behaviour at high Mach number.It is known, however, that the flow over the nose of the probe causes pressure variations such that it is some distance along the probe before the static pressure is equal to free stream static pressure. The NPL, in a series of tests at M = 1.6 showed that the pressure measured at a point situated less than 10 calibres (probe diameters) downstream of the beginning of the parallel portion of the probe was dependent on the shape of the nose.

Sensors based on materials with high refractive indices are desirable for sensing applications where a low penetration depth of the evanescent field into the covering analyte medium is required. To enhance the proportion of power carried into the covering medium while keeping the penetration depth low, a waveguiding device can be coated by a high-index film of metal oxide. We present numerical calculations as well as experimental comparisons between the evanescent fields of titanium dioxide-coated and uncoated waveguides in lithium niobate. The experiments were performed by using a Scanning Near-Field Optical Microscope (SNOM) in collection mode, which is an appropriate tool to measure and characterise evanescent fields. The coating of the waveguide leads to an enhancement of the power carried out into the covering medium by a factor 15 while the penetration depth remains the same in the range of a few 10 nm.

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