Terahertz virus-sized gold nanogap sensor
We demonstrated an ultra-sensitive terahertz virus detection method combined with virus-sized gold nanogaps filled with Al2O3. Large-area high-density 20 nm-gap rectangular loop structures, containing a resonant frequency in the terahertz range, were fabricated on a 4-inch wafer using atomic layer l...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
De Gruyter
2023-01-01
|
| Series: | Nanophotonics |
| Subjects: | |
| Online Access: | https://doi.org/10.1515/nanoph-2022-0706 |
| _version_ | 1811171923634159616 |
|---|---|
| author | Ji Gangseon Kim Hwan Sik Cha Seong Ho Lee Hyoung-Taek Kim Hye Ju Lee Sang Woon Ahn Kwang Jun Kim Kyoung-Ho Ahn Yeong Hwan Park Hyeong-Ryeol |
| author_facet | Ji Gangseon Kim Hwan Sik Cha Seong Ho Lee Hyoung-Taek Kim Hye Ju Lee Sang Woon Ahn Kwang Jun Kim Kyoung-Ho Ahn Yeong Hwan Park Hyeong-Ryeol |
| author_sort | Ji Gangseon |
| collection | DOAJ |
| description | We demonstrated an ultra-sensitive terahertz virus detection method combined with virus-sized gold nanogaps filled with Al2O3. Large-area high-density 20 nm-gap rectangular loop structures, containing a resonant frequency in the terahertz range, were fabricated on a 4-inch wafer using atomic layer lithography. When target viruses with a 60 nm diameter were located on the nanogaps, we observed a significant redshift of the resonant peak already with an average number of about 100 viruses per unit loop due to the strong field confinement and enhancement near the gap. Furthermore, when the virus was tightly attached to an etched gap like a bridge connecting metals, its sensitivity is doubled compared to the unetched gap, which resulted in 400% more resonance frequency shift per single virus particle than our previous work. Full-wave simulations and theoretical calculations based on modal expansions were in good agreement with the experiments, revealing that the resonant transmission spectrum was mostly determined by the change in refractive index in a two-dimensional-like optical hotspot near the nanogap. A further step could be taken to increase sensitivity by tuning nanogap-loops to the absorption frequencies associated with the intermolecular vibrational modes of the viruses and fingerprinting them as well. |
| first_indexed | 2024-04-10T17:22:17Z |
| format | Article |
| id | doaj.art-0a44d562f49045a7aa8dd71e35e556bc |
| institution | Directory Open Access Journal |
| issn | 2192-8614 |
| language | English |
| last_indexed | 2024-04-10T17:22:17Z |
| publishDate | 2023-01-01 |
| publisher | De Gruyter |
| record_format | Article |
| series | Nanophotonics |
| spelling | doaj.art-0a44d562f49045a7aa8dd71e35e556bc2023-02-05T08:27:17ZengDe GruyterNanophotonics2192-86142023-01-0112114715410.1515/nanoph-2022-0706Terahertz virus-sized gold nanogap sensorJi Gangseon0Kim Hwan Sik1Cha Seong Ho2Lee Hyoung-Taek3Kim Hye Ju4Lee Sang Woon5Ahn Kwang Jun6Kim Kyoung-Ho7Ahn Yeong Hwan8Park Hyeong-Ryeol9Department of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan449419, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan449419, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Research Institute for Nanoscale Science and Technology, Chungbuk National University, Cheongju28644, Republic of KoreaDepartment of Physics, Department of Energy Systems Research, Ajou University, Suwon16499, Republic of KoreaDepartment of Physics, Ulsan National Institute of Science and Technology (UNIST), Ulsan449419, Republic of KoreaWe demonstrated an ultra-sensitive terahertz virus detection method combined with virus-sized gold nanogaps filled with Al2O3. Large-area high-density 20 nm-gap rectangular loop structures, containing a resonant frequency in the terahertz range, were fabricated on a 4-inch wafer using atomic layer lithography. When target viruses with a 60 nm diameter were located on the nanogaps, we observed a significant redshift of the resonant peak already with an average number of about 100 viruses per unit loop due to the strong field confinement and enhancement near the gap. Furthermore, when the virus was tightly attached to an etched gap like a bridge connecting metals, its sensitivity is doubled compared to the unetched gap, which resulted in 400% more resonance frequency shift per single virus particle than our previous work. Full-wave simulations and theoretical calculations based on modal expansions were in good agreement with the experiments, revealing that the resonant transmission spectrum was mostly determined by the change in refractive index in a two-dimensional-like optical hotspot near the nanogap. A further step could be taken to increase sensitivity by tuning nanogap-loops to the absorption frequencies associated with the intermolecular vibrational modes of the viruses and fingerprinting them as well.https://doi.org/10.1515/nanoph-2022-0706atomic layer lithographynanogaprefractive index sensingterahertz sensingterahertz time-domain spectroscopyvirus |
| spellingShingle | Ji Gangseon Kim Hwan Sik Cha Seong Ho Lee Hyoung-Taek Kim Hye Ju Lee Sang Woon Ahn Kwang Jun Kim Kyoung-Ho Ahn Yeong Hwan Park Hyeong-Ryeol Terahertz virus-sized gold nanogap sensor Nanophotonics atomic layer lithography nanogap refractive index sensing terahertz sensing terahertz time-domain spectroscopy virus |
| title | Terahertz virus-sized gold nanogap sensor |
| title_full | Terahertz virus-sized gold nanogap sensor |
| title_fullStr | Terahertz virus-sized gold nanogap sensor |
| title_full_unstemmed | Terahertz virus-sized gold nanogap sensor |
| title_short | Terahertz virus-sized gold nanogap sensor |
| title_sort | terahertz virus sized gold nanogap sensor |
| topic | atomic layer lithography nanogap refractive index sensing terahertz sensing terahertz time-domain spectroscopy virus |
| url | https://doi.org/10.1515/nanoph-2022-0706 |
| work_keys_str_mv | AT jigangseon terahertzvirussizedgoldnanogapsensor AT kimhwansik terahertzvirussizedgoldnanogapsensor AT chaseongho terahertzvirussizedgoldnanogapsensor AT leehyoungtaek terahertzvirussizedgoldnanogapsensor AT kimhyeju terahertzvirussizedgoldnanogapsensor AT leesangwoon terahertzvirussizedgoldnanogapsensor AT ahnkwangjun terahertzvirussizedgoldnanogapsensor AT kimkyoungho terahertzvirussizedgoldnanogapsensor AT ahnyeonghwan terahertzvirussizedgoldnanogapsensor AT parkhyeongryeol terahertzvirussizedgoldnanogapsensor |