Semiclassical dynamics of light beams supported by adiabatically tapered nanofibers

M. Sumetsky

doi:10.1117/12.714258

14 February 2007 Semiclassical dynamics of light beams supported by adiabatically tapered nanofibers

M. Sumetsky

Proceedings Volume 6452, Laser Resonators and Beam Control IX; 64520R (2007) https://doi.org/10.1117/12.714258
Event: Lasers and Applications in Science and Engineering, 2007, San Jose, California, United States

Abstract

An optical microfiber with the diameter significantly less than the radiation wavelength ~ 1 micron is often called a nanofiber (NF). The fundamental mode of a NF consists primarily of an evanescent field propagating in the ambient medium outside a NF. Any deformation of a NF changes the evanescent field. If a NF is thin enough, even a very small deformation may cause dramatic changes of the evanescent field structure. The simplest types of deformation of a uniform NF are bending and tapering. The structure of evanescent field and optics of radiation loss in bent uniform microfibers is understood quite well. It is determined by an effective potential barrier terminated by a caustic surface, which separates the tunneling and classically allowed regions. Tunneling through the barrier determines the radiation loss. Alternatively, for an adiabatically tapered microfiber, called a nanotaper (NT), a similar potential barrier of finite width cannot be introduced. Instead, the radiation loss in a NT takes place in small neighborhood of focal circumferences of the evanescent field, while a NT is lossless elsewhere. More specifically, for a NT, the mentioned caustic surface becomes complex and can intersect real space along certain lines only. These lines are the focal circumferences where the radiating modes and the guiding mode are split off. As examples, conical and biconical NTs with characteristic shapes are considered. The theoretically predicted interference between the guiding and radiating components of the evanescent field are confirmed by the beam propagation method (BPM) numerical modeling. The derived analytical expressions for radiation loss are in a good agreement with BPM calculations. Finally, a simple estimate formula for radiation loss of a NT is suggested.

Citation Download Citation

M. Sumetsky "Semiclassical dynamics of light beams supported by adiabatically tapered nanofibers", Proc. SPIE 6452, Laser Resonators and Beam Control IX, 64520R (14 February 2007); https://doi.org/10.1117/12.714258

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

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
10 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Beam propagation method

Waveguides

Wave propagation

Radio propagation

Geometrical optics

Nanofibers

Electromagnetism

Show All Keywords

Keywords/Phrases

Search In:

Publication Years