Limit to the orbital angular momentum per unit energy in a light beam thatcan be focussed onto a small particle

Authors
Courtial, J Padgett, MJ
Citation
J. Courtial et Mj. Padgett, Limit to the orbital angular momentum per unit energy in a light beam thatcan be focussed onto a small particle, OPT COMMUN, 173(1-6), 2000, pp. 269-274
Citations number
10
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Optics & Acoustics
Journal title
OPTICS COMMUNICATIONS
ISSN journal
00304018 → ACNP
Volume
173
Issue
1-6
Year of publication
2000
Pages
269 - 274
Database
ISI
SICI code
0030-4018(20000101)173:1-6<269:LTTOAM>2.0.ZU;2-B
Abstract
Within a ray-optical approximation we show that there is a limit to the orb itaI angular momentum per unit energy that can be focussed onto a small par ticle. This limit depends solely on the geometry of the focussing optics an d the size of the particle and is independent of the wavelength of the ligh t. (C) 2000 Elsevier Science B.V. All rights reserved.