title: Lateral heterojunctions within monolayer MoSe2-WSe2 semiconductors.
abstract: Heterojunctions between three-dimensional (3D) semiconductors with different bandgaps are the basis of modern light-emitting diodes, diode lasers and high-speed transistors. Creating analogous heterojunctions between different 2D semiconductors would enable band engineering within the 2D plane and open up new realms in materials science, device physics and engineering. Here we demonstrate that seamless high-quality in-plane heterojunctions can be grown between the 2D monolayer semiconductors MoSe2 and WSe2. The junctions, grown by lateral heteroepitaxy using physical vapour transport, are visible in an optical microscope and show enhanced photoluminescence. Atomically resolved transmission electron microscopy reveals that their structure is an undistorted honeycomb lattice in which substitution of one transition metal by another occurs across the interface. The growth of such lateral junctions will allow new device functionalities, such as in-plane transistors and diodes, to be integrated within a single atomically thin layer.
authors.affiliation: 1] Department of Physics, University of Washington, Seattle, Washington 98195, USA [2].
authors.forename: Chunming
authors.initials: C
authors.lastname: Huang
authors.affiliation: 1] Department of Physics, University of Washington, Seattle, Washington 98195, USA [2].
authors.forename: Sanfeng
authors.initials: S
authors.lastname: Wu
authors.affiliation: 1] Department of Physics, University of Warwick, Coventry, CV4 7AL, UK [2].
authors.forename: Ana M
authors.initials: AM
authors.lastname: Sanchez
authors.affiliation: Department of Physics, University of Warwick, Coventry, CV4 7AL, UK.
authors.forename: Jonathan J P
authors.initials: JJ
authors.lastname: Peters
authors.affiliation: Department of Physics, University of Warwick, Coventry, CV4 7AL, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Beanland
authors.affiliation: Department of Material Science and Engineering, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Jason S
authors.initials: JS
authors.lastname: Ross
authors.affiliation: Department of Physics, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Pasqual
authors.initials: P
authors.lastname: Rivera
authors.affiliation: Department of Physics and Center of Theoretical and Computational Physics, University of Hong Kong, Hong Kong, China.
authors.forename: Wang
authors.initials: W
authors.lastname: Yao
authors.affiliation: Department of Physics, University of Washington, Seattle, Washington 98195, USA.
authors.forename: David H
authors.initials: DH
authors.lastname: Cobden
authors.affiliation: 1] Department of Physics, University of Washington, Seattle, Washington 98195, USA [2] Department of Material Science and Engineering, University of Washington, Seattle, Washington 98195, USA.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Xu