title: Active control of all-fibre graphene devices with electrical gating.
abstract: Active manipulation of light in optical fibres has been extensively studied with great interest because of its compatibility with diverse fibre-optic systems. While graphene exhibits a strong electro-optic effect originating from its gapless Dirac-fermionic band structure, electric control of all-fibre graphene devices remains still highly challenging. Here we report electrically manipulable in-line graphene devices by integrating graphene-based field effect transistors on a side-polished fibre. Ion liquid used in the present work critically acts both as an efficient gating medium with wide electrochemical windows and transparent over-cladding facilitating light-matter interaction. Combined study of unique features in gate-variable electrical transport and optical transition at monolayer and randomly stacked multilayer graphene reveals that the device exhibits significant optical transmission change (>90%) with high efficiency-loss figure of merit. This subsequently modifies nonlinear saturable absorption characteristics of the device, enabling electrically tunable fibre laser at various operational regimes. The proposed device will open promising way for actively controlled optoelectronic and nonlinear photonic devices in all-fibre platform with greatly enhanced graphene-light interaction.
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Eun Jung
authors.initials: EJ
authors.lastname: Lee
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Choi
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Hwanseong
authors.initials: H
authors.lastname: Jeong
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Nam Hun
authors.initials: NH
authors.lastname: Park
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Woongbin
authors.initials: W
authors.lastname: Yim
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Mi Hye
authors.initials: MH
authors.lastname: Kim
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Jae-Ku
authors.initials: JK
authors.lastname: Park
authors.affiliation: Soft Innovative Materials Research Center, Korea Institute of Science and Technology (KIST), 92 Chudong-ro, Bongdong-eup, Jeonbuk 565-905, Republic of Korea.
authors.forename: Suyeon
authors.initials: S
authors.lastname: Son
authors.affiliation: Soft Innovative Materials Research Center, Korea Institute of Science and Technology (KIST), 92 Chudong-ro, Bongdong-eup, Jeonbuk 565-905, Republic of Korea.
authors.forename: Sukang
authors.initials: S
authors.lastname: Bae
authors.affiliation: Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-747, Republic of Korea.
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Nano Photonics Research Center, KIST, 5, Hwarang-ro 14-gil, Seongbuk-gu, Seoul 136-791, Republic of Korea.
authors.forename: Kwanil
authors.initials: K
authors.lastname: Lee
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Yeong Hwan
authors.initials: YH
authors.lastname: Ahn
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Kwang Jun
authors.initials: KJ
authors.lastname: Ahn
authors.affiliation: Department of Chemistry, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151-747, Republic of Korea.
authors.forename: Byung Hee
authors.initials: BH
authors.lastname: Hong
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Ji-Yong
authors.initials: JY
authors.lastname: Park
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Fabian
authors.initials: F
authors.lastname: Rotermund
authors.affiliation: Department of Physics and Department of Energy Systems Research, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Dong-Il
authors.initials: DI
authors.lastname: Yeom