Measurement of Energy Distribution of Output Electrons From a Microchannel Plate Based on Vacuum Photodiode

Junkun Huang,Yunfei Lei,Dong Wang,Yong Wang,Pokun Deng,Houzhi Cai,Jinyuan Liu

doi:10.1109/access.2021.3121718

Junkun Huang, Yunfei Lei + Show 5 more

Open Access

https://doi.org/10.1109/access.2021.3121718

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Abstract

The energy distribution of output electrons (EDOE) from a microchannel plate (MCP) is measured using electrons emitted by a vacuum photodiode excited by a 266 nm Ti-sapphire femtosecond laser. The photoelectrons emitted from the photocathode are focused on a specific location of the MCP by a magnetic lens. While exist an enough voltage difference between the two ends of MCP, the energy distribution curve of output electrons form MCP can be obtained by analyzing the data as function of the bias voltage applied to the charge collector. The result shows that the energy distribution curve obtained by this means consists of a sharp and a long tail when using pulse light source. The most probable electron energy (MPE) is 12.64 eV and the full width at half maximum (FWHM) of the energy distribution curve is about 29.23 eV while the applied voltage difference is 700 V in the experimental setup. The MPE is 10.63 eV and the FWHM of the energy distribution is 22.436 eV in simulation. The measured curve is consistent with the expectation from simulation.

Highlights

Microchannel plate (MCP) as current multiplying optical device plays an important role in image intensifier tubes for imaging and intensification of the photoelectron image [1]
To better understand the characteristics of the MCP, the MCP is studied from different perspectives, such as the secondary electron emission from the surface of different metals or components [3]–[6] and the energy distribution of output electrons (EDOE) from the MCP [7]–[11]
The energy distribution curve is found to consist of a sharp main peak and a long tail extending over a wide energy range

Summary

Introduction

Microchannel plate (MCP) as current multiplying optical device plays an important role in image intensifier tubes for imaging and intensification of the photoelectron image [1]. When applying an enough voltage difference between the two ends of MCP, the incident primary electron striking on the inside surface of the microchannel produces a number of secondary electrons as output. The width of the energy distribution curve was found to depend on the applied voltage on the MCP and the lengthto-diameter ratio of the channel [8].

Results

Conclusion