A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator
A novel micron-range displacement sensor based on a whispering-gallery mode (WGM) microcapillary resonator filled with a nematic liquid crystal (LC) and a magnetic nanoparticle- coated fiber half-taper is proposed and experimentally demonstrated. In the proposed device, the tip of a fiber half-taper...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-10-01
|
| Series: | Sensors |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1424-8220/22/21/8312 |
| _version_ | 1827645513906782208 |
|---|---|
| author | Zhe Wang Arun Kumar Mallik Fangfang Wei Zhuochen Wang Anuradha Rout Qiang Wu Yuliya Semenova |
| author_facet | Zhe Wang Arun Kumar Mallik Fangfang Wei Zhuochen Wang Anuradha Rout Qiang Wu Yuliya Semenova |
| author_sort | Zhe Wang |
| collection | DOAJ |
| description | A novel micron-range displacement sensor based on a whispering-gallery mode (WGM) microcapillary resonator filled with a nematic liquid crystal (LC) and a magnetic nanoparticle- coated fiber half-taper is proposed and experimentally demonstrated. In the proposed device, the tip of a fiber half-taper coated with a thin layer of magnetic nanoparticles (MNPs) moves inside the LC-filled microcapillary resonator along its axis. The input end of the fiber half-taper is connected to a pump laser source and due to the thermo-optic effect within the MNPs, the fiber tip acts as point heat source increasing the temperature of the LC material in its vicinity. An increase in the LC temperature leads to a decrease in its effective refractive index, which in turn causes spectral shift of the WGM resonances monitored in the transmission spectrum of the coupling fiber. The spectral shift of the WGMs is proportional to the displacement of the MNP-coated tip with respect to the microcapillary’s light coupling point. The sensor’s operation is simulated considering heat transfer in the microcapillary filled with a LC material having a negative thermo-optic coefficient. The simulations are in a good agreement with the WGMs spectral shift observed experimentally. A sensitivity to displacement of 15.44 pm/µm and a response time of 260 ms were demonstrated for the proposed sensor. The device also shows good reversibility and repeatability of response. The proposed micro-displacement sensor has potential applications in micro-manufacturing, precision measurement and medical instruments. |
| first_indexed | 2024-03-09T18:40:18Z |
| format | Article |
| id | doaj.art-a22203e4a27a456c802a71d82f94c708 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-09T18:40:18Z |
| publishDate | 2022-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-a22203e4a27a456c802a71d82f94c7082023-11-24T06:46:05ZengMDPI AGSensors1424-82202022-10-012221831210.3390/s22218312A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary ResonatorZhe Wang0Arun Kumar Mallik1Fangfang Wei2Zhuochen Wang3Anuradha Rout4Qiang Wu5Yuliya Semenova6Photonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, D07 ADY7 Dublin, IrelandTyndall National Institute, University College Cork, Lee Maltings, Dyke Parade, T12 YN60 Cork, IrelandPhotonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, D07 ADY7 Dublin, IrelandPhotonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, D07 ADY7 Dublin, IrelandPhotonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, D07 ADY7 Dublin, IrelandDepartment of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle upon Tyne NE1 8ST, UKPhotonics Research Centre, School of Electrical and Electronic Engineering, Technological University Dublin, D07 ADY7 Dublin, IrelandA novel micron-range displacement sensor based on a whispering-gallery mode (WGM) microcapillary resonator filled with a nematic liquid crystal (LC) and a magnetic nanoparticle- coated fiber half-taper is proposed and experimentally demonstrated. In the proposed device, the tip of a fiber half-taper coated with a thin layer of magnetic nanoparticles (MNPs) moves inside the LC-filled microcapillary resonator along its axis. The input end of the fiber half-taper is connected to a pump laser source and due to the thermo-optic effect within the MNPs, the fiber tip acts as point heat source increasing the temperature of the LC material in its vicinity. An increase in the LC temperature leads to a decrease in its effective refractive index, which in turn causes spectral shift of the WGM resonances monitored in the transmission spectrum of the coupling fiber. The spectral shift of the WGMs is proportional to the displacement of the MNP-coated tip with respect to the microcapillary’s light coupling point. The sensor’s operation is simulated considering heat transfer in the microcapillary filled with a LC material having a negative thermo-optic coefficient. The simulations are in a good agreement with the WGMs spectral shift observed experimentally. A sensitivity to displacement of 15.44 pm/µm and a response time of 260 ms were demonstrated for the proposed sensor. The device also shows good reversibility and repeatability of response. The proposed micro-displacement sensor has potential applications in micro-manufacturing, precision measurement and medical instruments.https://www.mdpi.com/1424-8220/22/21/8312whispering gallery modescapillarydisplacement sensorthermo-optic tuning |
| spellingShingle | Zhe Wang Arun Kumar Mallik Fangfang Wei Zhuochen Wang Anuradha Rout Qiang Wu Yuliya Semenova A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator Sensors whispering gallery modes capillary displacement sensor thermo-optic tuning |
| title | A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator |
| title_full | A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator |
| title_fullStr | A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator |
| title_full_unstemmed | A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator |
| title_short | A Micron-Range Displacement Sensor Based on Thermo-Optically Tuned Whispering Gallery Modes in a Microcapillary Resonator |
| title_sort | micron range displacement sensor based on thermo optically tuned whispering gallery modes in a microcapillary resonator |
| topic | whispering gallery modes capillary displacement sensor thermo-optic tuning |
| url | https://www.mdpi.com/1424-8220/22/21/8312 |
| work_keys_str_mv | AT zhewang amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT arunkumarmallik amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT fangfangwei amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT zhuochenwang amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT anuradharout amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT qiangwu amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT yuliyasemenova amicronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT zhewang micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT arunkumarmallik micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT fangfangwei micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT zhuochenwang micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT anuradharout micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT qiangwu micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator AT yuliyasemenova micronrangedisplacementsensorbasedonthermoopticallytunedwhisperinggallerymodesinamicrocapillaryresonator |