Open AccessQuantum efficiency of transmission-mode graded bandgap AlxGa1-xAs/GaAs photocathode
Author(s) -
Yang Yang,
Weiwei Cao,
Peng Xu,
Yonglin Bai,
Bingli Zhu,
Bo Wang,
Junjun Qin,
Bai X
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1676/1/012220
Subject(s) - photocathode , optoelectronics , quantum efficiency , band gap , materials science , layer (electronics) , wavelength , transmission (telecommunications) , optics , gallium arsenide , quantum well , electron , physics , telecommunications , nanotechnology , computer science , quantum mechanics , laser
Graded bandgap Al x Ga 1-x As/GaAs photocathode with enhanced quantum efficiency is analyzed in this study. We present the relevant quantum efficiency equations by solving onedimensional continuity equations for transmission-mode graded bandgap Al x Ga 1-x As/GaAs and standard AlGaAs/GaAs photocathodes. The results show that the built-in electrical field from bandgap gradation efficiently collects photogenerated electrons in the buffer layer such that quantum efficiencies in the short regions are improved in transmission-mode Al x Ga 1-x As/GaAs photocathode. The results also show that a thinner buffer layer improves the short-wavelength response of transmission-mode photocathode. Increasing the active layer thickness improves long-wavelength responses but reduces short-wavelength responses. The method presented in this work may provide better estimate of performance and guide the optimum design of graded bandgap Al x Ga 1-x As/GaAs photocathode.