{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T15:56:58Z","timestamp":1772726218871,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,3,31]],"date-time":"2023-03-31T00:00:00Z","timestamp":1680220800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of Shaanxi Province under grant","award":["2023-JC-YB-587"],"award-info":[{"award-number":["2023-JC-YB-587"]}]},{"name":"Natural Science Foundation of Shaanxi Province under grant","award":["20YFZCGX00440"],"award-info":[{"award-number":["20YFZCGX00440"]}]},{"name":"Natural Science Foundation of Shaanxi Province under grant","award":["2021SYS-04"],"award-info":[{"award-number":["2021SYS-04"]}]},{"name":"Key Technologies R &amp; D Program of Tianjin","award":["2023-JC-YB-587"],"award-info":[{"award-number":["2023-JC-YB-587"]}]},{"name":"Key Technologies R &amp; D Program of Tianjin","award":["20YFZCGX00440"],"award-info":[{"award-number":["20YFZCGX00440"]}]},{"name":"Key Technologies R &amp; D Program of Tianjin","award":["2021SYS-04"],"award-info":[{"award-number":["2021SYS-04"]}]},{"name":"Shaanxi Key Laboratory of Deep Space Exploration Intelligent Information Technology","award":["2023-JC-YB-587"],"award-info":[{"award-number":["2023-JC-YB-587"]}]},{"name":"Shaanxi Key Laboratory of Deep Space Exploration Intelligent Information Technology","award":["20YFZCGX00440"],"award-info":[{"award-number":["20YFZCGX00440"]}]},{"name":"Shaanxi Key Laboratory of Deep Space Exploration Intelligent Information Technology","award":["2021SYS-04"],"award-info":[{"award-number":["2021SYS-04"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We design a graded-index ring-core fiber with a GeO2-doped silica ring core and SiO2 cladding. This fiber structure can inhibit the effect of spin-orbit coupling to mitigate the power transfer among different modes and eventually enhance the orbital angular momentum (OAM) mode purity. By changing the high-index ring core from the step-index to parabolic graded-index profile, the purity of the OAM1,1 mode can be improved from 86.48% to 94.43%, up by 7.95%. The proposed fiber features a flexible structure, which can meet different requirements for mode order, effective mode area, etc. Simulation results illustrate that the parabolic-index ring-core fiber is promising in enhancing the OAM mode purity, which could potentially reduce the channel crosstalk in mode-division-multiplexed optical communication systems.<\/jats:p>","DOI":"10.3390\/s23073641","type":"journal-article","created":{"date-parts":[[2023,3,31]],"date-time":"2023-03-31T08:27:27Z","timestamp":1680251247000},"page":"3641","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Parabolic-Index Ring-Core Fiber Supporting High-Purity Orbital Angular Momentum Modes"],"prefix":"10.3390","volume":"23","author":[{"given":"Yuanpeng","family":"Liu","sequence":"first","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7876-5722","authenticated-orcid":false,"given":"Yingning","family":"Wang","sequence":"additional","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"given":"Wenpu","family":"Geng","sequence":"additional","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"given":"Wenqian","family":"Zhao","sequence":"additional","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"given":"Hao","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"given":"Weigang","family":"Zhang","sequence":"additional","affiliation":[{"name":"Institute of Modern Optics, Nankai University, Tianjin 300350, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2325-2254","authenticated-orcid":false,"given":"Zhongqi","family":"Pan","sequence":"additional","affiliation":[{"name":"Department of Electrical & Computer Engineering, University of Louisiana at Lafayette, Lafayette, LA 70504, USA"}]},{"given":"Yang","family":"Yue","sequence":"additional","affiliation":[{"name":"School of Information and Communications Engineering, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1364\/AOP.6.000413","article-title":"Space-division multiplexing: The next frontier in optical communication","volume":"6","author":"Li","year":"2014","journal-title":"Adv. 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