Real-time terahertz imaging over a standoff distance (>25meters)

  title={Real-time terahertz imaging over a standoff distance (>25meters)},
  author={Alan Wei Min Lee and Qi Qin and Sushil Kumar and Benjamin S. Williams and Q. Y. Hu and John Louis Reno},
  journal={Applied Physics Letters},
The authors demonstrate the use of a terahertz quantum cascade laser (QCL) for real-time imaging in transmission mode at a standoff distance of 25meters. Lasing frequency was selected for optimum transmission within an atmospheric window at ∼4.9THz. Coarse frequency selection was made by design of the QCL gain medium. Finer selection (to within 0.1THz) was made by judicious choice of laser cavity length to adjust facet losses and therefore lasing threshold bias, in order to overlap the peak… 

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