title: Mono- to few-layered graphene oxide embedded randomness assisted microcavity amplified spontaneous emission source.
abstract: The realization of optoelectronic devices using two-dimensional materials such as graphene and its intermediate product graphene oxide (GO) is extremely challenging owing to the zero band gap of the former. Here, a novel amplified spontaneous emission (ASE) system based on a GO-embedded all-dielectric one-dimensional photonic crystal (1DPhC) micro-resonator is presented. The mono- to few-layered GO sheet is inserted within a microcavity formed by two 5-bilayered SiO2/SnO2 Bragg reflectors. Significantly enhanced photoluminescence (PL) emission of GO embedded in 1DPhC is explicated by studying the electric field confined within the micro-resonator using the transfer matrix method. The inherent randomness, due to fabrication limitations, in the on-average periodic 1DPhC is exploited to further enhance the PL of the optically active micro-resonator. The 1DPhC and randomness assisted field confinement reduces the ASE threshold of the mono- to few-layered weak emitter making the realization of an ASE source feasible. Consequently, ASE at the microcavity resonance and at the low-frequency band-edge of photonic stop-band is demonstrated. Variation of the detection angle from 5° to 30°, with respect to the sample surface normal allows reallocation of the defect mode ASE peak over a spectral range of 558-542 nm, making the GO-incorporated 1DPhC a novel and attractive system for integrated optic applications.
authors.affiliation: Department of Physics, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
authors.forename: Pratyusha
authors.initials: P
authors.lastname: Das
authors.forename: Rishi
authors.initials: R
authors.lastname: Maiti
authors.forename: Prahalad K
authors.initials: PK
authors.lastname: Barman
authors.forename: Samit K
authors.initials: SK
authors.lastname: Ray
authors.forename: Bhaktha B N
authors.initials: BB
authors.lastname: Shivakiran