We report on [001]InP nanowires grown by metalorganic vapor phase epitaxy directly on (001)InP substrates. Characterization by scanning electron microscopy and transmission electron microscopy reveals wires with nearly square cross sections and a perfect zinc-blende crystalline structure that is free of stacking faults. Photoluminescence measurements of single [001] nanowires exhibit a narrow and intense emission peak at approximately 1.4eV, whereas ⟨111⟩B grown reference wires show additional broad luminescence peaks at lower energy. The origin of this uncommon wire growth direction [001] is discussed as a means of controlled formation of [00l]-oriented nanowires on (001) substrates.

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We describe cameras incorporating focal plane arrays of Geiger-mode avalanche photodiodes (GmAPDs) that enable 3-D imaging in laser radar (LADAR) systems operating at wavelengths near 1.0 and 1.5 μm. GmAPDs based on the InGaAsP material system achieve single-photon sensitivity at every pixel of the array and are hybridized to custom CMOS ROICs providing 0.25 ns timing resolution. We present camera-level performance for photon detection efficiency and dark count rate, along with a survey of the evolution of performance for a substantial number of 32 × 32 cameras. We then describe a temporal statistical analysis of the array-level dark count behavior that distinguishes between Poissonian intrinsic dark count rate and non-Poissonian crosstalk counts. We also report the spatial analysis of crosstalk events to complement the statistical temporal analysis. Differences between cameras optimized for the two different wavelengths-1.0 and 1.5 μm-are noted, particularly with regard to crosstalk behavior.Index Terms-Single-photon, avalanche photodiode (APD), Geiger mode, laser radar (LADAR), three-dimensional (3-D) imaging, short-wave infrared (SWIR).

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