eprintid: 10074068
rev_number: 16
eprint_status: archive
userid: 608
dir: disk0/10/07/40/68
datestamp: 2019-05-21 12:36:41
lastmod: 2021-11-08 00:17:13
status_changed: 2019-05-21 12:36:41
type: article
metadata_visibility: show
creators_name: Nagar, J
creators_name: Chaky, RJ
creators_name: Pantoja, MF
creators_name: McKinley, AF
creators_name: Werner, DH
title: Optimization of Far-Field Radiation From Impedance-Loaded Nanoloops Accelerated by an Exact Analytical Formulation
ispublished: pub
divisions: UCL
divisions: B04
divisions: C05
divisions: F46
keywords: Antenna theory, Loop antennas, Optimization,
Nanotechnology, Submillimeter wave technology.
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: Impedance loading is a common technique
traditionally used in the RF to enhance the performance of an
antenna, but its application in the optical regime is not as
rigorously studied. This is mainly due to a lack of exact analytical
expressions that can be used to rapidly predict the radiation
properties of loaded nanoantennas. This paper will derive a set of
useful analytical expressions for the far-field radiation properties
of loop antennas loaded with an arbitrary number of lumped
impedances that are valid from the RF to optical regimes. The
analytical expressions will be validated with full-wave solvers and
can be evaluated more than 100x faster. The ability to perform
such rapid evaluations enables, for the first time, large-scale
single- and multi-objective optimizations. A series of optimizations
reveal that electrically small super-directive antennas can be
achieved at a variety of far field angles through capacitive loading,
paving the way for a pattern reconfigurable antenna. In addition,
gains of greater than 3 dB can be achieved for electrically small
antennas over a fractional bandwidth of 28%. Finally, it is shown
that impedance loading can be used to achieve circularly polarized
radiation from a single loop.
date: 2019-03
date_type: published
publisher: IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
official_url: https://doi.org/10.1109/TAP.2018.2888727
oa_status: green
full_text_type: other
language: eng
primo: open
primo_central: open_green
article_type_text: Article
verified: verified_manual
elements_id: 1642481
doi: 10.1109/TAP.2018.2888727
lyricists_name: McKinley, Arnold
lyricists_id: AFMCK30
actors_name: McKinley, Arnold
actors_id: AFMCK30
actors_role: owner
full_text_status: public
publication: IEEE Transactions on Antennas and Propagation
volume: 67
number: 3
pagerange: 1448-1458
pages: 11
issn: 1558-2221
citation:        Nagar, J;    Chaky, RJ;    Pantoja, MF;    McKinley, AF;    Werner, DH;      (2019)    Optimization of Far-Field Radiation From Impedance-Loaded Nanoloops Accelerated by an Exact Analytical Formulation.                   IEEE Transactions on Antennas and Propagation , 67  (3)   pp. 1448-1458.    10.1109/TAP.2018.2888727 <https://doi.org/10.1109/TAP.2018.2888727>.       Green open access   
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10074068/1/nanoloop_impedanceLoaded_vFinal_clean.pdf