Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber
Terahertz metamaterial absorbers (TMAs) are gaining considerable attention due to their unique characteristics. Graphene-based absorbers are a subclass of TMAs that exhibit tunable absorption characteristics for myriad applications. This paper proposes a TMA consisting of two layers of graphene in a...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2025-12-01
|
| Series: | Results in Optics |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666950125001002 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849252184911249408 |
|---|---|
| author | Omid Mohsen Daraei Pejman Rezaei Seyed Amin Khatami Pouria Zamzam Saswat Mohapatra Bhargav Appasani Shiva Khani |
| author_facet | Omid Mohsen Daraei Pejman Rezaei Seyed Amin Khatami Pouria Zamzam Saswat Mohapatra Bhargav Appasani Shiva Khani |
| author_sort | Omid Mohsen Daraei |
| collection | DOAJ |
| description | Terahertz metamaterial absorbers (TMAs) are gaining considerable attention due to their unique characteristics. Graphene-based absorbers are a subclass of TMAs that exhibit tunable absorption characteristics for myriad applications. This paper proposes a TMA consisting of two layers of graphene in a cross-shaped structure where the absorption can be modified by altering the chemical potential of the graphene layers. A quarter-wave impedance transformer has been utilized to attain optimal absorption in the vicinity of the central frequency of this absorber. The normalized input admittance’s real and imaginary parts should be approximately tuned to 1 and 0 around the central frequency to achieve the ideal absorption rate. Also, the transmission line theory has been considered to verify the absorption level achieved around the central frequency. The conductivity of the graphene layer is changed by altering the levels of chemical potential; the Fermi levels for the upper and lower layers of the graphene cross-shaped THz absorber have been considered 1 eV and 0.3 eV, respectively, to achieve maximum absorption. Therefore, the bandwidth of this absorber reached 1.74 THz, around 7 THz as the central frequency. The proposed asymmetric stacked graphene structure provides broadband, polarization-insensitive, and electrically tunable absorption around 7 THz, making it highly suitable for applications such as THz imaging, sensing, and electromagnetic signature reduction technologies. Compared to prior designs, it offers improved bandwidth, tunability, and angular stability, making it a compact and practical solution for next-generation terahertz systems. |
| format | Article |
| id | doaj-art-94303c718e484a7b9ec230f668b5ebdc |
| institution | Kabale University |
| issn | 2666-9501 |
| language | English |
| publishDate | 2025-12-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Results in Optics |
| spelling | doaj-art-94303c718e484a7b9ec230f668b5ebdc2025-08-20T03:56:42ZengElsevierResults in Optics2666-95012025-12-012110087210.1016/j.rio.2025.100872Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorberOmid Mohsen Daraei0Pejman Rezaei1Seyed Amin Khatami2Pouria Zamzam3Saswat Mohapatra4Bhargav Appasani5Shiva Khani6Department of Electrical and Computer Engineering, University of Houston, Calhoun Road, Houston, TX 77204, USAElectrical and Computer Engineering Faculty, Semnan University, Semnan, Iran; Corresponding author.Electrical and Computer Engineering Faculty, Semnan University, Semnan, IranElectrical and Computer Engineering Faculty, Semnan University, Semnan, IranDepartment of Electrical and Computer Engineering, University of Houston, Calhoun Road, Houston, TX 77204, USASchool of Electronics Engineering, KIIT University, Bhubaneswar 751024, IndiaElectrical and Computer Engineering Faculty, Semnan University, Semnan, IranTerahertz metamaterial absorbers (TMAs) are gaining considerable attention due to their unique characteristics. Graphene-based absorbers are a subclass of TMAs that exhibit tunable absorption characteristics for myriad applications. This paper proposes a TMA consisting of two layers of graphene in a cross-shaped structure where the absorption can be modified by altering the chemical potential of the graphene layers. A quarter-wave impedance transformer has been utilized to attain optimal absorption in the vicinity of the central frequency of this absorber. The normalized input admittance’s real and imaginary parts should be approximately tuned to 1 and 0 around the central frequency to achieve the ideal absorption rate. Also, the transmission line theory has been considered to verify the absorption level achieved around the central frequency. The conductivity of the graphene layer is changed by altering the levels of chemical potential; the Fermi levels for the upper and lower layers of the graphene cross-shaped THz absorber have been considered 1 eV and 0.3 eV, respectively, to achieve maximum absorption. Therefore, the bandwidth of this absorber reached 1.74 THz, around 7 THz as the central frequency. The proposed asymmetric stacked graphene structure provides broadband, polarization-insensitive, and electrically tunable absorption around 7 THz, making it highly suitable for applications such as THz imaging, sensing, and electromagnetic signature reduction technologies. Compared to prior designs, it offers improved bandwidth, tunability, and angular stability, making it a compact and practical solution for next-generation terahertz systems.http://www.sciencedirect.com/science/article/pii/S2666950125001002AbsorberMetamaterialGrapheneMulti-bandPolarization-insensitiveTerahertz |
| spellingShingle | Omid Mohsen Daraei Pejman Rezaei Seyed Amin Khatami Pouria Zamzam Saswat Mohapatra Bhargav Appasani Shiva Khani Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber Results in Optics Absorber Metamaterial Graphene Multi-band Polarization-insensitive Terahertz |
| title | Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber |
| title_full | Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber |
| title_fullStr | Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber |
| title_full_unstemmed | Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber |
| title_short | Absorption bandwidth enhancement technique using stacked unequal cross-shaped graphene absorber |
| title_sort | absorption bandwidth enhancement technique using stacked unequal cross shaped graphene absorber |
| topic | Absorber Metamaterial Graphene Multi-band Polarization-insensitive Terahertz |
| url | http://www.sciencedirect.com/science/article/pii/S2666950125001002 |
| work_keys_str_mv | AT omidmohsendaraei absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT pejmanrezaei absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT seyedaminkhatami absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT pouriazamzam absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT saswatmohapatra absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT bhargavappasani absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber AT shivakhani absorptionbandwidthenhancementtechniqueusingstackedunequalcrossshapedgrapheneabsorber |