Abstract: A multiple quantum well layer is sandwiched between two core waveguide layers, which are, in turn, sandwiched by two cladding layers. This layering is deposited on a substrate with a metal contact and the top cladding layer is formed so as to form at least two parallel channels with metal contacts. The refractive indices of the various materials comprising the layers are chosen such that the cladding layers and the multiple quantum well layer have refractive indices which are less than the refractive index of the core waveguide layers, but which are different from one another. In operation, an electric field is applied to the structure via metal contacts on the parallel channels. Depending on the magnitude of the electric field the optical signal may be switched from one channel to the other channel and depending on the magnitude and direction of the electric field and the intensity of the optical signal, the optical signal may be switched from the upper waveguide to the lower waveguide.

Abstract: The use of a highly stable, lattice-matched barrier layer grown epitaxially on a suitable substrate, and permitting the subsequent epitaxial growth of a thin high-temperature superconducting film with optimized properties.

Abstract: A material sample is rubbed with an abrasive material until streaking appears in the abrasive indicating that the material sample has become embedded in the abrasive and the abrasive material then analyzed using qualitative and quantitative chemical analysis.