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Title: Directional excitation without breaking reciprocity

Abstract

Here, we propose a mechanism for directional excitation without breaking reciprocity. This is achieved by embedding an impedance matched parity-time symmetric potential in a three-port system. The amplitude distribution within the gain and loss regions is strongly influenced by the direction of the incoming field. Consequently, the excitation of the third port is contingent on the direction of incidence while transmission in the main channel is immune. This design improves the four-port directional coupler scheme, as there is no need to implement an anechoic termination to one of the ports.

Authors:
 [1];  [2];  [2];  [3];  [4]
  1. Univ. of California, Berkeley, CA (United States). NSF Nanoscale Science and Engineering Center; Univ. of Texas Rio Grande Valley, Brownsville, TX (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  2. Univ. of California, Berkeley, CA (United States). NSF Nanoscale Science and Engineering Center
  3. Univ. of California, Berkeley, CA (United States). Dept. of Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  4. Univ. of California, Berkeley, CA (United States). NSF Nanoscale Science and Engineering Center; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1414764
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
New Journal of Physics
Additional Journal Information:
Journal Volume: 18; Journal Issue: 9; Journal ID: ISSN 1367-2630
Publisher:
IOP Publishing
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; pt symmetry; acoustics; directional excitation

Citation Formats

Ramezani, Hamidreza, Dubois, Marc, Wang, Yuan, Shen, Y. Ron, and Zhang, Xiang. Directional excitation without breaking reciprocity. United States: N. p., 2016. Web. doi:10.1088/1367-2630/18/9/095001.
Ramezani, Hamidreza, Dubois, Marc, Wang, Yuan, Shen, Y. Ron, & Zhang, Xiang. Directional excitation without breaking reciprocity. United States. doi:10.1088/1367-2630/18/9/095001.
Ramezani, Hamidreza, Dubois, Marc, Wang, Yuan, Shen, Y. Ron, and Zhang, Xiang. 2016. "Directional excitation without breaking reciprocity". United States. doi:10.1088/1367-2630/18/9/095001. https://www.osti.gov/servlets/purl/1414764.
@article{osti_1414764,
title = {Directional excitation without breaking reciprocity},
author = {Ramezani, Hamidreza and Dubois, Marc and Wang, Yuan and Shen, Y. Ron and Zhang, Xiang},
abstractNote = {Here, we propose a mechanism for directional excitation without breaking reciprocity. This is achieved by embedding an impedance matched parity-time symmetric potential in a three-port system. The amplitude distribution within the gain and loss regions is strongly influenced by the direction of the incoming field. Consequently, the excitation of the third port is contingent on the direction of incidence while transmission in the main channel is immune. This design improves the four-port directional coupler scheme, as there is no need to implement an anechoic termination to one of the ports.},
doi = {10.1088/1367-2630/18/9/095001},
journal = {New Journal of Physics},
number = 9,
volume = 18,
place = {United States},
year = 2016,
month = 9
}

Journal Article:
Free Publicly Available Full Text
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