Evaluation of a HgCdTe e-APD based detector for 2 μm CO DIAL application.

Benefiting from close to ideal amplification properties (high gain, low dark current, and low excess noise factor), HgCdTe electron initiated avalanche photodiode (e-APD) technology exhibits state of the art sensitivity, thus being especially relevant for applications relying on low light level detection, such as LIDAR (Light Detection And Ranging). In addition, the tunable gap of the HgCdTe alloy enables coverage of the short wavelength infrared (SWIR) and especially the 2 μm spectral range. For these two reasons, a HgCdTe e-APD based detector is a promising candidate for future differential absorption LIDAR missions targeting greenhouse gas absorption bands in SWIR.

Partially localized hybrid surface plasmon mode for thin-film semiconductor infrared photodetection.

We use numerical simulations to show that a suitably dimensioned periodic arrangement of vertical metallic metal-dielectric-metal nanocavities supports a hybrid plasmonic mode whose spatial electric field distribution is suitable for use in infrared photodetectors based on an unpatterned semiconductor thin-film absorbing layer. The partially localized nature of the hybrid mode offers reduced sensitivity to the angle of incoming light and smaller pixel sizes compared with surface plasmonic modes coupled by diffraction.

High-Curie-temperature ferromagnetism in self-organized Ge1-xMnx nanocolumns.

The emerging field of spintronics would be dramatically boosted if room-temperature ferromagnetism could be added to semiconductor nanostructures that are compatible with silicon technology. Here, we report a high-TC (>400K) ferromagnetic phase of (Ge,Mn) epitaxial layer. The manganese content is 6%, and careful structural and chemical analyses show that the Mn distribution is strongly inhomogeneous: we observe eutectoid growth of well-defined Mn-rich nanocolumns surrounded by a Mn-poor matrix.