Novel diagnostic techniques for investigations into energy and matter transport in dynamic systems
type: CreativeWork
description: Light-matter interactions are fundamental to many technologies used today. They are complex, non-linear processes sensitive to the properties of the source, material, mechanisms, and environment in which they interact. In order to control a process, its key features must be measurable and characterised. To date, most efforts in doing so follow either empirical or theoretical approaches, requiring existing or potential users of laser technology to invest significant time and money in their attempted use. In this work a novel diagnostics platform is theorised for the study of light-matter interactions by assessing energy transfer within a process relative to certain performance attributes e.g. ablation efficiency (kg/W), coupling momentum efficiency (N.s/W) and kinetic energy ratio (plume energy over pulse energy) with the aim of producing widely relatable results which significantly lessen the need for heavily empirical or theoretical work. The missing element of the diagnostic platform, a torsion balance, capable of measuring impulsive forces and mass loss, was designed, constructed, and calibrated to the ultra precision standards required to measure nano-scale forces including a force and mass-loss resolution of nN and µg respectively. The tool was then used to characterise the behaviour of some ‘generic’ pulsed nano-second light matter inactions with varying source parameters such as total energy input (58.6 mJ to 468.8 mJ), repetition rate (5 kHz to 40 kHz), temporal pulse shape (up to 500 ns duration and 50 kW peak power), and materials (aluminium, silicon, and PVC), as well different environments (air and vacuum) and processing strategies (scanning and single point drilling). Three dimensional processing maps were then produced using the torsion balance, laser, environment, and material data to represent the quantitative and qualitative nature of results. When convoluted or stitched together, the maps uniquely enable the optimisation of process specific perform…
abstract: Light-matter interactions are fundamental to many technologies used today. They are complex, non-linear processes sensitive to the properties of the source, material, mechanisms, and environment in which they interact. In order to control a process, its key features must be measurable and characterised. To date, most efforts in doing so follow either empirical or theoretical approaches, requiring existing or potential users of laser technology to invest significant time and money in their attempted use. In this work a novel diagnostics platform is theorised for the study of light-matter interactions by assessing energy transfer within a process relative to certain performance attributes e.g. ablation efficiency (kg/W), coupling momentum efficiency (N.s/W) and kinetic energy ratio (plume energy over pulse energy) with the aim of producing widely relatable results which significantly lessen the need for heavily empirical or theoretical work. The missing element of the diagnostic platform, a torsion balance, capable of measuring impulsive forces and mass loss, was designed, constructed, and calibrated to the ultra precision standards required to measure nano-scale forces including a force and mass-loss resolution of nN and µg respectively. The tool was then used to characterise the behaviour of some ‘generic’ pulsed nano-second light matter inactions with varying source parameters such as total energy input (58.6 mJ to 468.8 mJ), repetition rate (5 kHz to 40 kHz), temporal pulse shape (up to 500 ns duration and 50 kW peak power), and materials (aluminium, silicon, and PVC), as well different environments (air and vacuum) and processing strategies (scanning and single point drilling). Three dimensional processing maps were then produced using the torsion balance, laser, environment, and material data to represent the quantitative and qualitative nature of results. When convoluted or stitched together, the maps uniquely enable the optimisation of process specific perform…
author: El Gabbani, Nadeem
language: eng
keywords: Space, Propulsion, Force Balance, Force Measurement, Laser, Laser Processing, Laser Matter Interactions, Torsion Balance, Ultrashort Laser, Ultrafast Laser, Laser Manufacturing, Laser Propulsion, Energy Saving, LMI, Laser Ablation
license: https://www.rioxx.net/licenses/all-rights-reserved/
date published: 2021-06-14
date modified: 2026-07-22T22:24:30Z
provider: Cambridge University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Cambridge

PropertyValue
property ID: DOI
value: 10.17863/CAM.83926