title: Ultrafast optical nonlinearity of multi-layered graphene synthesized by the interface growth process.
abstract: We propose a novel photonic application as well as an optical tool to verify the crystallinity of interface-grown graphene demonstrating passive mode-locked lasers. The interface growth process enables the formation of multi-layered graphene at an interface of substrate and catalyst, therefore directly onto the targeted substrate without a transfer process. The synthesized graphene is characterized using Raman spectroscopy and x-ray photoelectron spectroscopy before ultrashort pulse formation to confirm the validity of the process for high-speed photonic applications of graphene. The resultant pulses have a repetition rate, pulse duration, RF extinction ratio of 14.01 MHz, 1.0 ps, and ∼35 dB, respectively.
authors.affiliation: Future Convergence Research Division, Korea Institute of Science and Technology, Seoul 136-791, Korea.
authors.forename: Won-Jun
authors.initials: WJ
authors.lastname: Kim
authors.forename: You Min
authors.initials: YM
authors.lastname: Chang
authors.forename: Junsu
authors.initials: J
authors.lastname: Lee
authors.forename: Dongseok
authors.initials: D
authors.lastname: Kang
authors.forename: Ju Han
authors.initials: JH
authors.lastname: Lee
authors.forename: Yong-Won
authors.initials: YW
authors.lastname: Song