title: All-optical graphene oxide humidity sensors.
abstract: The optical characteristics of graphene oxide (GO) were explored to design and fabricate a GO-based optical humidity sensor. GO film was coated onto a SU8 polymer channel waveguide using the drop-casting technique. The proposed sensor shows a high TE-mode absorption at 1550 nm. Due to the dependence of the dielectric properties of the GO film on water content, this high TE-mode absorption decreases when the ambient relative humidity increases. The proposed sensor shows a rapid response (<1 s) to periodically interrupted humid air flow. The transmission of the proposed sensor shows a linear response of 0.553 dB/% RH in the range of 60% to 100% RH.
authors.affiliation: Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia. wghglim@hotmail.com.
authors.forename: Weng Hong
authors.initials: WH
authors.lastname: Lim
authors.affiliation: Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia. yuenkiat@siswa.um.edu.my.
authors.forename: Yuen Kiat
authors.initials: YK
authors.lastname: Yap
authors.affiliation: Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia. wuyi@um.edu.my.
authors.forename: Wu Yi
authors.initials: WY
authors.lastname: Chong
authors.affiliation: Photonics Research Centre, University of Malaya, Kuala Lumpur 50603, Malaysia. harith@um.edu.my.
authors.forename: Harith
authors.initials: H
authors.lastname: Ahmad