Zinc-containing optical glass materials with a refractive index nd between 1. Further, at least some of the disclosed systems and methods employ a memory to store the gathered seismic data. The effect of the well casing is determined based upon the plurality of current source vectors and the at least one property of the well casing. In various embodiments, the well region includes a number of recombination centers between the Si\u2014Ge layer and the insulation layer. Apparatus for microchannel cooling include integrated microchannel heat sink devices and fluid distribution manifold structures that are designed to provide uniform flow and distribution of coolant fluid and minimize pressure drops along coolant flow paths.