• Corpus ID: 208527004

Quantum Efficiency Enhancement by Mie Resonance from GaAs Photocathodes Structured with Surface Nanopillar Arrays

  title={Quantum Efficiency Enhancement by Mie Resonance from GaAs Photocathodes Structured with Surface Nanopillar Arrays},
  author={Xincun Peng and Zhidong Wang and Yun Qin Liu and Dennis M. Manos and Matthew Poelker and Marcy Stutzman and Bin Tang and Shukui Zhang and Ji-jun Zou},
  journal={arXiv: Optics},
A new type of negative electron affinity (NEA) photocathode based on GaAs nanopillar array (NPA) Mie-type resonators was demonstrated for the first time. For visible wavelengths, the Mie resonances in GaAs NPA reduced light reflectivity to less than 6 percent compared to a typical value great then 35 percent. Other benefits of NPA resonators include an enhanced density of optical states due to increased light concentration and increased electron emission area. These features resulted in… 

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