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A black phosphorus photo-detector for multispectral, high-resolution imaging

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 نشر من قبل Michael Engel
 تاريخ النشر 2014
  مجال البحث فيزياء
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Black phosphorus is a layered semiconductor that is intensely researched in view of applications in optoelectronics. In this Letter, we investigate a multi-layer black phosphorus photo-detector that is capable of acquiring high-contrast (V>0.9) images both in the visible ({lambda}_{VIS}=532nm) as well as in the infrared ({lambda}_{IR}=1550nm) spectral regime. In a first step, by using photocurrent microscopy, we map the active area of the device and we characterize responsivity and gain. In a second step, by deploying the black phosphorus device as a point-like detector in a confocal microsope setup, we acquire diffraction-limited optical images with sub-micron resolution. The results demonstrate the usefulness of black phosphorus as an optoelectronic material for hyperspectral imaging applications.

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