Uniform performance of high-efficiency room-temperature GaInAsSb/GaSb photodiodes for 1.75 < lambda < 2.2 mum.
A group of 126 experimental, packaged, backilluminated, 1.75-2.2-microm wavelength, GaInAsSb mesa (~85-microm diameter) photodetectors have been assembled and evaluated. Average room-temperature properties were peak quantum efficiency, 86%; zero-bias capacitance, 3.9 pF; dark current at -0.5-V bias, 7.4 microA.
Heavy metal fluoride glasses and fibers: A review
A comprehensive summary is provided on the subject of heavy metal fluoride glasses. This includes discussions on glass compositions, preparation, structure, fiber drawing characteristics, and intrinsic and extrinsic optical properties. Other relevant glass and fiber characteristics such as strength, durability, and thermal Shock resistance are also outlined. Particular emphasis is given to the measurements of optical attenuation in fluoride glasses and their potential for use in ultralow-loss fiber optic waveguides. An excellent bibliography of recent work in the area of heavy metal fluoride glasses has been generated for those seeking more detailed information on this topic.
Glass formation in ionic systems
In the past five years, glass formation has been observed in many chemical systems involving zirconium tetrafluoride1–5. These ionic glasses were unexpected as no theory of glass formation had predicted their occurrence. Most common glasses can be explained by the Zachariazen theory6 which gives criteria for vitreous structures with highly directed three-dimensional bond arrays, according to energy and kinetic considerations. However, the theory does not encompass some new amorphous systems such as amorphous germanium or the new ionic glasses. I review here the structural and energetic conditions for glass formation in ionic systems with particular reference to fluoride glasses.