title: Selective Amplification of the Primary Exciton in a MoS_{2} Monolayer.
abstract: Optoelectronics applications for transition-metal dichalcogenides are still limited by weak light absorption and their complex exciton modes are easily perturbed by varying excitation conditions because they are inherent in atomically thin layers. Here, we propose a method of selectively amplifying the primary exciton (A^{0}) among the exciton complexes in monolayer MoS_{2} via cyclic reexcitation of cavity-free exciton-coupled plasmon propagation. This was implemented by partially overlapping a Ag nanowire on a MoS_{2} monolayer separated by a thin SiO_{2} spacer. Exciton-coupled plasmons in the nanowire enhance the A^{0} radiation in MoS_{2}. The cumulative amplification of emission enhancement by cyclic plasmon traveling reaches approximately twentyfold selectively for the A^{0}, while excluding other B exciton and multiexciton by significantly reduced band filling, without oscillatory spectra implying plasmonic cavity effects.
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Hyun Seok
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Min Su
authors.initials: MS
authors.lastname: Kim
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.|Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Youngjo
authors.initials: Y
authors.lastname: Jin
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Gang Hee
authors.initials: GH
authors.lastname: Han
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.|Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.|Department of Physics, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Young Hee
authors.initials: YH
authors.lastname: Lee
authors.affiliation: Center for Integrated Nanostructure Physics (CINAP), Institute for Basic Science (IBS), Sungkyunkwan University, Suwon 440-746, Korea.|Department of Energy Science, Sungkyunkwan University, Suwon 440-746, Korea.
authors.forename: Jeongyong
authors.initials: J
authors.lastname: Kim