{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T10:38:04Z","timestamp":1792751884526,"version":"4.5.0"},"reference-count":44,"publisher":"Wiley","issue":"20","license":[{"start":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:00:00Z","timestamp":1791936000000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:00:00Z","timestamp":1791936000000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2023R1A2C2002777"],"award-info":[{"award-number":["2023R1A2C2002777"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS\u20102024\u201000416583"],"award-info":[{"award-number":["RS\u20102024\u201000416583"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Nanophotonics"],"published-print":{"date-parts":[[2026,10,27]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    Microring resonators (MRRs) are key components of photonic integrated circuits for filtering, modulation, and spectroscopic sensing. In the mid\u2010infrared (mid\u2010IR), asymmetric resonances are attractive because their steep local spectral transitions can enhance wavelength discrimination in compact resonant devices. Here, we demonstrate geometry\u2010controlled asymmetric resonances in a germanium\u2010on\u2010insulator (Ge\u2010OI) MRR at 4.2\u00a0\u03bcm by introducing a single subwavelength air hole into the bus\u2010waveguide coupling region as a localized phase perturbation. Effective\u2010index analysis shows that the hole geometry estimates a controllable phase shift \u0394\n                    <jats:italic>\u03d5<\/jats:italic>\n                    of up to 0.82\u03c0 rad, enabling systematic evolution from a nearly symmetric Lorentzian resonance to a strongly asymmetric Fano\u2010like response. The results are explained by a phase\u2010modified transmission model and are described using a weighted Fano\u2013Lorentz formalism, which explains the resonance evolution in the (\n                    <jats:italic>\u03b4<\/jats:italic>\n                    ,\n                    <jats:italic>\u03b7<\/jats:italic>\n                    ) parameter space. Among our devices, the optimum point is achieved at an intermediate perturbation rather than at the maximum \u0394\n                    <jats:italic>\u03d5<\/jats:italic>\n                    , yielding a loaded quality factor\n                    <jats:italic>Q<\/jats:italic>\n                    of 2.15\u00a0\u00d7\u00a010\n                    <jats:sup>5<\/jats:sup>\n                    and a slope rate of 435\u00a0dB\/nm. These results show that compact air\u2010hole perturbation can tune high\u2010\n                    <jats:italic>Q<\/jats:italic>\n                    asymmetric resonances in Ge\u2010OI mid\u2010IR photonics, where the useful high\u2010slope regime is determined by a balance among phase\u2010induced asymmetry, linewidth preservation, coupling condition, and local transmission contrast.\n                  <\/jats:p>","DOI":"10.1002\/nap2.70321","type":"journal-article","created":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T05:14:46Z","timestamp":1792041286000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Phase\u2010Controlled Asymmetric Resonances for Enhanced Spectral Slope in a Ge\u2010OI Microring Resonator at 4.2\u00a0\u03bcm"],"prefix":"10.1002","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8110-2241","authenticated-orcid":false,"given":"Jinha","family":"Lim","sequence":"first","affiliation":[{"name":"School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST)  Daejeon South Korea"},{"name":"Center for Quantum Technology Korea Institute of Science and Technology (KIST)  Seoul South\u00a0Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2517-4408","authenticated-orcid":false,"given":"SangHyeon","family":"Kim","sequence":"additional","affiliation":[{"name":"School of Electrical Engineering Korea Advanced Institute of Science and Technology (KAIST)  Daejeon South Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,10,14]]},"reference":[{"key":"e_1_2_8_2_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41378\u2010024\u201000697\u20102"},{"key":"e_1_2_8_3_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010022\u201032417\u20107"},{"key":"e_1_2_8_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.optlaseng.2005.04.015"},{"key":"e_1_2_8_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.aca.2020.04.015"},{"key":"e_1_2_8_6_1","doi-asserted-by":"publisher","DOI":"10.1364\/OE.19.018945"},{"key":"e_1_2_8_7_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41598\u2010023\u201032313\u20100"},{"key":"e_1_2_8_8_1","doi-asserted-by":"publisher","DOI":"10.1364\/IONT.2012.ITh5B.1"},{"key":"e_1_2_8_9_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.scib.2018.05.038"},{"key":"e_1_2_8_10_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41578\u2010024\u201000668\u2010z"},{"key":"e_1_2_8_11_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41586\u2010025\u201009620\u20109"},{"key":"e_1_2_8_12_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010019\u201010282\u20101"},{"key":"e_1_2_8_13_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41467\u2010023\u201044628\u20107"},{"key":"e_1_2_8_14_1","doi-asserted-by":"publisher","DOI":"10.1063\/5.0157177"},{"key":"e_1_2_8_15_1","doi-asserted-by":"publisher","DOI":"10.1063\/5.0077394"},{"key":"e_1_2_8_16_1","doi-asserted-by":"publisher","DOI":"10.1002\/lpor.202500099"},{"key":"e_1_2_8_17_1","doi-asserted-by":"publisher","DOI":"10.1038\/nphoton.2010.171"},{"key":"e_1_2_8_18_1","doi-asserted-by":"publisher","DOI":"10.1002\/lpor.202501738"},{"key":"e_1_2_8_19_1","doi-asserted-by":"publisher","DOI":"10.1364\/OE.524895"},{"key":"e_1_2_8_20_1","doi-asserted-by":"publisher","DOI":"10.1364\/PRJ.495076"},{"key":"e_1_2_8_21_1","doi-asserted-by":"publisher","DOI":"10.1364\/OL.43.002885"},{"key":"e_1_2_8_22_1","doi-asserted-by":"publisher","DOI":"10.1063\/5.0149324"},{"key":"e_1_2_8_23_1","doi-asserted-by":"publisher","DOI":"10.1063\/5.0033070"},{"key":"e_1_2_8_24_1","doi-asserted-by":"publisher","DOI":"10.1109\/JLT.2023.3235745"},{"key":"e_1_2_8_25_1","doi-asserted-by":"publisher","DOI":"10.1063\/5.0220382"},{"key":"e_1_2_8_26_1","doi-asserted-by":"publisher","DOI":"10.1021\/acsphotonics.4c01185"},{"key":"e_1_2_8_27_1","doi-asserted-by":"publisher","DOI":"10.1021\/acssensors.4c00941"},{"key":"e_1_2_8_28_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41377\u2010025\u201001803\u20103"},{"key":"e_1_2_8_29_1","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRev.124.1866"},{"key":"e_1_2_8_30_1","doi-asserted-by":"publisher","DOI":"10.1038\/nphoton.2017.142"},{"key":"e_1_2_8_31_1","doi-asserted-by":"publisher","DOI":"10.1126\/science.1234407"},{"key":"e_1_2_8_32_1","doi-asserted-by":"publisher","DOI":"10.1088\/0031\u20108949\/74\/2\/020"},{"key":"e_1_2_8_33_1","doi-asserted-by":"publisher","DOI":"10.1515\/nanoph\u20102018\u20100229"},{"key":"e_1_2_8_34_1","doi-asserted-by":"publisher","DOI":"10.1364\/OE.504912"},{"key":"e_1_2_8_35_1","doi-asserted-by":"publisher","DOI":"10.1063\/1.5124092"},{"key":"e_1_2_8_36_1","doi-asserted-by":"publisher","DOI":"10.1364\/OE.390966"},{"key":"e_1_2_8_37_1","doi-asserted-by":"publisher","DOI":"10.1515\/nanoph\u20102022\u20100394"},{"key":"e_1_2_8_38_1","doi-asserted-by":"publisher","DOI":"10.1038\/s41377\u2010025\u201002076\u20106"},{"key":"e_1_2_8_39_1","doi-asserted-by":"publisher","DOI":"10.3788\/COL202523.053602"},{"key":"e_1_2_8_40_1","doi-asserted-by":"publisher","DOI":"10.1109\/JLT.1985.1074291"},{"key":"e_1_2_8_41_1","doi-asserted-by":"publisher","DOI":"10.1364\/JOSAA.11.000963"},{"key":"e_1_2_8_42_1","doi-asserted-by":"publisher","DOI":"10.1364\/AO.52.004884"},{"key":"e_1_2_8_43_1","doi-asserted-by":"publisher","DOI":"10.1002\/qute.202300199"},{"key":"e_1_2_8_44_1","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevB.87.125118"},{"key":"e_1_2_8_45_1","doi-asserted-by":"publisher","DOI":"10.1103\/RevModPhys.82.2257"}],"container-title":["Nanophotonics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/nap2.70321","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/nap2.70321","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/nap2.70321","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T09:42:32Z","timestamp":1792748552000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/nap2.70321"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,10,14]]},"references-count":44,"journal-issue":{"issue":"20","published-print":{"date-parts":[[2026,10,27]]}},"alternative-id":["10.1002\/nap2.70321"],"URL":"https:\/\/doi.org\/10.1002\/nap2.70321","archive":["Portico"],"relation":{},"ISSN":["2192-8614","2192-8614"],"issn-type":[{"value":"2192-8614","type":"print"},{"value":"2192-8614","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,10,14]]},"assertion":[{"value":"2026-08-25","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-10-05","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-10-14","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70321"}}