Near-threshold harmonics from a femtosecond enhancement cavity-based EUV source: effects of multiple quantum pathways on spatial profile and yield

Publication Type
Journal Article
Year of Publication
2011
Authors
Hammond, T. J.
Mills, Arthur K.
Jones, David J.
Name of Publication
Optics Express
Volume
19
Pagination
24871 - 24883
Issue
25
Date Published
2011/12/05/
ISBN Number
1094-4087
Keywords
frequency comb, generation, ionization, khz, mhz, repetition rate, ultraviolet
Abstract

We investigate the photon flux and far-field spatial profiles for near-threshold harmonics produced with a 66 MHz femtosecond enhancement cavity-based EUV source operating in the tight-focus regime. The effects of multiple quantum pathways in the far-field spatial profile and harmonic yield show a strong dependence on gas jet dynamics, particularly nozzle diameter and position. This simple system, consisting of only a 700 mW Ti:Sapphire oscillator and an enhancement cavity produces harmonics up to 20 eV with an estimated 30-100 mu W of power (intracavity) and > 1 mu W (measured) of power spectrally-resolved and out-coupled from the cavity. While this power is already suitable for applications, a quantum mechanical model of the system indicates substantial improvements should be possible with technical upgrades. (C) 2011 Optical Society of America


Source URL: https://phas.ubc.ca/near-threshold-harmonics-femtosecond-enhancement-cavity-based-euv-source-effects-multiple-quantum-pa