Simulation of short pulse photoemission in a microdiode with implications for optimal beam brightness

Title:	Simulation of short pulse photoemission in a microdiode with implications for optimal beam brightness
Author:	Árnason, Hákon Örn orcid.org/0000-0002-6074-6598 Torfason, Kristinn Manolescu, Andrei orcid.org/0000-0002-0713-4664 Valfells, Ágúst 4 authors Show fewer authors
Date:	2024
Language:	English
Scope:	1-8
University/Institute:	Háskólinn í Reykjavík Reykjavik University
School:	School of Technology Tæknisvið
Department:	Department of Engineering Verkfræðideild
ISSN:	0018-9383 1557-9646
DOI:	10.1109/TED.2024.3351096
Subject:	Electrical and Electronic Engineering; Electronic, Optical and Magnetic Materials; Rafmagnsverkfræði; Rafeindaverkfræði; Rafsegulfræði; Eðlisfræði
URI:	https://hdl.handle.net/20.500.11815/4716
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Abstract: Molecular dynamics simulations, with full Coulomb interaction, are used to model short-pulse photoemission from a finite area in a microdiode. We demonstrate three emission regimes, source-limited emission, space-charge-limited emission for short pulses, and space-charge-limited emission for the steady state. We show that beam brightness is at a maximum during the transition from the source-limited emission regime to the space-charge-limited emission regime for short pulses. From our simulations, it is apparent that the emitter spot size is an important factor when estimating the critical charge density for short-pulse electron emission and that simple capacitive models may considerably underestimate the total charge emitted.