Quantum efficiency of InP field-assisted photocathodes

Abstract

Reflection-mode quantum efficiencies have been calculated for the p-InP bias-assisted photoemitter (TE cathode) and have been found to be consistent with experimental data. The calculations, using Monte Carlo techniques, consider the transport of photogenerated electrons to the surface as well as the transmission of electrons at the surface into vacuum. Dependence of the predicted yield upon bias voltage and doping is discussed. Acceptor doping in the mid 1016/cm3 range is indicated as a good choice for a high quantum efficiency photocathode.

Analytic modeling of transit-time device drift regions with field-dependent transport coefficients

“…This is accomplished by the use of a collision time correction in the relationship between the time-varying small-signal velocity and the tim.e-varying small-signal field (eqn (35)). The inclusion of this relaxation time is consistent with the assumed static velocity-field characteristic in the limit It must be stated that inertial effects in the injection process[25, 26} have not been included nor have velocity overshoot effects [12,27] been included. Velocity overshoot occurs in the low-field portion of the drift region and will almost certainly degrade BARITT performance.…”

Monte Carlo simulations of GaN cold cathodes

“…photocathodes [12]. The electric field profile through the p-GaN layer is calculated using the simple Schottky barrier model of the GaN/LaB interface [13].…”

Comparison of quantum and collection efficiency of field‐assisted uniform‐doping and exponential‐doping GaN nanowire cathodes

“…The field‐assisted method not only can bend electrons' motion track after emission but also can accelerate the electrons to the collecting side. Theoretical calculations of the photoelectric emission have initially proved that providing an electric field is an effective method to increase the QE of transmissive GaAs planar photocathodes, which is 2.2 times higher than the QE without the assistance of electric field . For GaAs photocathodes within external electric filed, polarization is much more adequate than that of the conventional NEA GaAs electron source …”

“…Theoretical calculations of the photoelectric emission have initially proved that providing an electric field is an effective method to increase the QE of transmissive GaAs planar photocathodes, which is 2.2 times higher than the QE without the assistance of electric field. 29,30 For GaAs photocathodes within external electric filed, polarization is much more adequate than that of the conventional NEA GaAs electron source. 31 Based on the fact that new low-dimensional materials have been widely used in optoelectronic devices, 32,33 here, we mainly study the effect of electron-trapping ability of nanowire photocathodes under external electric field.…”