title: Nanoforging Single Layer MoSe2 Through Defect Engineering with Focused Helium Ion Beams.
abstract: Development of devices and structures based on the layered 2D materials critically hinges on the capability to induce, control, and tailor the electronic, transport, and optoelectronic properties via defect engineering, much like doping strategies have enabled semiconductor electronics and forging enabled introduction the of iron age. Here, we demonstrate the use of a scanning helium ion microscope (HIM) for tailoring the functionality of single layer MoSe2 locally, and decipher associated mechanisms at the atomic level. We demonstrate He(+) beam bombardment that locally creates vacancies, shifts the Fermi energy landscape and increases the Young's modulus of elasticity. Furthermore, we observe for the first time, an increase in the B-exciton photoluminescence signal from the nanoforged regions at the room temperature. The approach for precise defect engineering demonstrated here opens opportunities for creating functional 2D optoelectronic devices with a wide range of customizable properties that include operating in the visible region.
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA.|The Procter and Gamble Company Winton Hill Business Center (WBHC), Cincinnati, OH 45224, USA.
authors.forename: Vighter
authors.initials: V
authors.lastname: Iberi
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Liangbo
authors.initials: L
authors.lastname: Liang
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, TN 37931, USA.
authors.forename: Anton V
authors.initials: AV
authors.lastname: Ievlev
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Stanford
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Ming-Wei
authors.initials: MW
authors.lastname: Lin
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Xufan
authors.initials: X
authors.lastname: Li
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Masoud
authors.initials: M
authors.lastname: Mahjouri-Samani
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, TN 37931, USA.
authors.forename: Stephen
authors.initials: S
authors.lastname: Jesse
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, TN 37931, USA.|Computer Science &Mathematics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Bobby G
authors.initials: BG
authors.lastname: Sumpter
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, TN 37931, USA.
authors.forename: Sergei V
authors.initials: SV
authors.lastname: Kalinin
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, USA.
authors.forename: David C
authors.initials: DC
authors.lastname: Joy
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
authors.forename: Kai
authors.initials: K
authors.lastname: Xiao
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Procter and Gamble Company Winton Hill Business Center (WBHC), Cincinnati, OH 45224, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Belianinov
authors.affiliation: Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.|The Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, TN 37931, USA.
authors.forename: Olga S
authors.initials: OS
authors.lastname: Ovchinnikova