title: Touch stimulated pulse generation in biomimetic single-layer graphene.
abstract: Detecting variation in contact pressure is a separate sensing mode in the human somatosensory system that differs from the detection of pressure magnitude. If pressure magnitude and variation sensing can be achieved simultaneously, an advanced biomimetic tactile system that better emulates human senses may be developed. We report on a novel single-layer graphene based artificial mechanoreceptor that generates a resistance pulse as the contact stimulus passes a specific threshold pressure, mimicking the generation of action potentials in a biological fast-adapting mechanoreceptor. The electric field from a flexible membrane gate electrode placed above a graphene channel raises the Fermi level from the valence band as pressure deflects the membrane. The threshold pressure is reached when the Fermi level crosses the Dirac point in the graphene energy band, which generates a sharp peak in the measured resistance. We found that by changing the gate potential it was possible to modulate the threshold pressure and using a series of graphene channels, a train of pulses were generated during a transient pressurizing stimulus demonstrating biomimetic behaviour.
authors.affiliation: Institute of Nano Science and Technology, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul, 04763, Republic of Korea. sbl22@hanyang.ac.kr.
authors.forename: Onejae
authors.initials: O
authors.lastname: Sul
authors.forename: Hyunsuk
authors.initials: H
authors.lastname: Chun
authors.forename: Eunseok
authors.initials: E
authors.lastname: Choi
authors.forename: Jungbong
authors.initials: J
authors.lastname: Choi
authors.forename: Kyeongwon
authors.initials: K
authors.lastname: Cho
authors.forename: Dongpyo
authors.initials: D
authors.lastname: Jang
authors.forename: Sungwoo
authors.initials: S
authors.lastname: Chun
authors.forename: Wanjun
authors.initials: W
authors.lastname: Park
authors.forename: Seung-Beck
authors.initials: SB
authors.lastname: Lee
mesh_terms: D040761:Biomimetic Materials; D004566:Electrodes; D006108:Graphite; D006801:Humans; D008465:Mechanoreceptors
chemical_list: D006108:Graphite