{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T00:57:01Z","timestamp":1760057821589,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,22]],"date-time":"2025-02-22T00:00:00Z","timestamp":1740182400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100007129","name":"Natural Science Foundation of Shandong Province","doi-asserted-by":"publisher","award":["ZR2023MF064"],"award-info":[{"award-number":["ZR2023MF064"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The conjoined split-ring resonator (Co-SRR) is proposed as the unit cell to construct terahertz (THz) metamaterial. The size and position of the gaps on both sides of the structure were adjusted, and the impact on the electromagnetic response to the incident THz wave was investigated via simulation. Results show that by properly controlling the structural asymmetry, the resonances can be tuned simultaneously or independently. The devices exhibit frequency shifts of up to 510 GHz, a tuning range of free spectral range (FSR) as wide as 613 GHz, and a high modulation depth (MD) of 93.4%. Additionally, a wide range of amplitude modulation can occur across multiple frequencies. Incorporating spatial asymmetry further enhances the performance, resulting in a high quality factor (Q) of 44.8 and a figure of merit (FOM) of 40.1. The impressive characteristics prove that Co-SRR-based metamaterial is a great candidate for applications in optical sensing, switching, filtering and programming devices.<\/jats:p>","DOI":"10.3390\/sym17030332","type":"journal-article","created":{"date-parts":[[2025,2,24]],"date-time":"2025-02-24T07:46:57Z","timestamp":1740383217000},"page":"332","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Role of Asymmetry on the Resonances of Conjoined Split-Ring Resonators"],"prefix":"10.3390","volume":"17","author":[{"given":"Mei","family":"Zhu","sequence":"first","affiliation":[{"name":"School of Physics and Electronic Engineering, Taishan University, Tai\u2019an 271021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xitao","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronic Engineering, Taishan University, Tai\u2019an 271021, China"},{"name":"School of Information Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lian","family":"Zhang","sequence":"additional","affiliation":[{"name":"School of Physics and Electronic Engineering, Taishan University, Tai\u2019an 271021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jiguo","family":"Geng","sequence":"additional","affiliation":[{"name":"School of Physics and Electronic Engineering, Taishan University, Tai\u2019an 271021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Physics and Electronic Engineering, Taishan University, Tai\u2019an 271021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"597","DOI":"10.1038\/nature05343","article-title":"Active terahertz metamaterial devices","volume":"444","author":"Chen","year":"2006","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1038\/nature09776","article-title":"A terahertz metamaterial with unnaturally high refractive index","volume":"470","author":"Choi","year":"2011","journal-title":"Nature"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Lee, D.K., Kang, J.H., Kwon, J., Lee, J.S., Lee, S., Woo, D.H., Kim, J.H., Song, C.S., Park, Q.H., and Seo, M. 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