Control of an orbital angular momentum of a Gaussian beam using zero intensity lines

V. V. Kotlyar; A. A. Kovalev; A. G. Nalimov

doi:10.1117/12.2631648

25 July 2022 Control of an orbital angular momentum of a Gaussian beam using zero intensity lines

V. V. Kotlyar, A. A. Kovalev, A. G. Nalimov

Proceedings Volume 12295, Optical Technologies for Telecommunications 2021; 1229508 (2022) https://doi.org/10.1117/12.2631648
Event: Nineteenth International Scientific and Technical Conference "Optical Technologies for Communications", 2021, Samara, Russian Federation

Abstract

We theoretically show how, using a cylindrical lens, a Gaussian beam with a finite number of parallel zero-intensity lines (edge dislocations) is transformed into a vortex beam that carries orbital angular momentum (OAM) and topological charge (TC). Remarkably, while the original beam is assumed to carry a non-zero OAM and have no TC, the latter is shown to appear during free-space propagation. Considering two parallel center-symmetric zero-intensity lines located as an example, we look into the dynamics of generating two intensity nulls at the double focal length: with increasing distance between the vertical zerointensity lines, two optical vortices are first generated on the horizontal axis, before converging at the origin and then diverging along the vertical axis. Irrespective of the between-line distance, such an optical vortex has TC = –2 at any distance from the optical axis, except for the original plane. With changing distance between the zero-intensity lines, the OAM that the beam carries is changing, taking positive and negative values, or a zero value at a certain between-line distance. We also show that if the number of zero-intensity lines is infinite, a vortex beam with finite OAM and infinite TC is generated.

Citation Download Citation

V. V. Kotlyar, A. A. Kovalev, and A. G. Nalimov "Control of an orbital angular momentum of a Gaussian beam using zero intensity lines", Proc. SPIE 12295, Optical Technologies for Telecommunications 2021, 1229508 (25 July 2022); https://doi.org/10.1117/12.2631648

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available