John Weiner

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Measurement of the transmitted intensity from a coherent monomode light source through a series of subwavelength slit arrays in Ag films, with varying array pitch and number of slits, demonstrates enhancement ͑suppression͒ by factors of as much as 6 ͑9͒ when normalized to the transmission efficiency of an isolated slit. Pronounced minima in the transmitted(More)
The angular diameters of a Orionis and o Ceti were measured at a wavelength of 11.15 km using the two-telescope Infrared Spatial Interferometer (ISI). Based on Ðtting the visibility data to uniform disk models, the diameter of a Orionis is 54.7 ^ 0.3 mas and that of o Ceti at phase 0.90 is 47.8 ^ 0.5 mas. These diameters are the most precise ever measured(More)
  • John Weiner
  • 2009
The passage of light through apertures much smaller than the wavelength of the light has proved to be a surprisingly subtle phenomenon. This report describes how modern developments in nanofabrication, coherent light sources, and numerical vector field simulations have led to the upending of early predictions from scalar diffraction theory and classical(More)
We analyze the physical-chemical surface properties of single-slit, single-groove subwavelength-structured silver films with high-resolution transmission electron microscopy and calculate exact solutions to Maxwell's equations corresponding to recent far-field interferometry experiments using these structures. Contrary to a recent suggestion the surface(More)
The size and variability of the continuum photosphere of o Ceti have been measured with 11 lm heterodyne interferometry to an accuracy of about 1%. Narrow bandwidths ($0.17 cm À1) were used to avoid spectral lines and measure continuum only. The resulting 11 lm diameter of o Cet is larger than the previously measured visible and near-infrared sizes. In(More)
Although competition between plants is usually asymmetric (i.e. larger plants have a disproportionate effect on smaller plants) almost all models of plant competition at the local level have assumed symmetric competition. We add a simple version of competitive asymmetry to the local density neighborhood models of plant interference and population dynamics(More)
We apply the technique of far-field interferometry to measure the properties of surface waves generated by two-dimensional (2D) single subwavelength slit-groove structures on gold films. The effective surface index of refraction n(surf) measured for the surface wave propagating over a distance of more than 12 mum is determined to be n(surf) = 1.016+/-0.004,(More)
The size of the continuum photospheres of Ori, Her, R Leo, and Cyg have been measured at 11 lm using heterodyne interferometry to accuracies as high as 1%. An assortment of narrow wavelength bands near 11 lm (each having a width $0.17 cm À1) were used to avoid spectral lines. The resulting apparent diameters for Ori and Her are $30% larger than measured(More)
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