title: Quality Heterostructures from Two-Dimensional Crystals Unstable in Air by Their Assembly in Inert Atmosphere.
abstract: Many layered materials can be cleaved down to individual atomic planes, similar to graphene, but only a small minority of them are stable under ambient conditions. The rest react and decompose in air, which has severely hindered their investigation and potential applications. Here we introduce a remedial approach based on cleavage, transfer, alignment, and encapsulation of air-sensitive crystals, all inside a controlled inert atmosphere. To illustrate the technology, we choose two archetypal two-dimensional crystals that are of intense scientific interest but are unstable in air: black phosphorus and niobium diselenide. Our field-effect devices made from their monolayers are conductive and fully stable under ambient conditions, which is in contrast to the counterparts processed in air. NbSe2 remains superconducting down to the monolayer thickness. Starting with a trilayer, phosphorene devices reach sufficiently high mobilities to exhibit Landau quantization. The approach offers a venue to significantly expand the range of experimentally accessible two-dimensional crystals and their heterostructures.
authors.forename: Y
authors.initials: Y
authors.lastname: Cao
authors.forename: A
authors.initials: A
authors.lastname: Mishchenko
authors.forename: G L
authors.initials: GL
authors.lastname: Yu
authors.forename: E
authors.initials: E
authors.lastname: Khestanova
authors.forename: A P
authors.initials: AP
authors.lastname: Rooney
authors.forename: E
authors.initials: E
authors.lastname: Prestat
authors.forename: A V
authors.initials: AV
authors.lastname: Kretinin
authors.affiliation: ∥Graphene Industries Ltd., 2 Tupelo Street, Manchester, M13 9HQ, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Blake
authors.forename: M B
authors.initials: MB
authors.lastname: Shalom
authors.forename: C
authors.initials: C
authors.lastname: Woods
authors.forename: J
authors.initials: J
authors.lastname: Chapman
authors.affiliation: ⊥Department of Physics, University of Warwick, Coventry CV4 7AL, United Kingdom.
authors.forename: G
authors.initials: G
authors.lastname: Balakrishnan
authors.forename: I V
authors.initials: IV
authors.lastname: Grigorieva
authors.forename: K S
authors.initials: KS
authors.lastname: Novoselov
authors.affiliation: #Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, F-38042 Grenoble, France.
authors.forename: B A
authors.initials: BA
authors.lastname: Piot
authors.affiliation: #Laboratoire National des Champs Magnétiques Intenses, CNRS-UJF-UPS-INSA, F-38042 Grenoble, France.
authors.forename: M
authors.initials: M
authors.lastname: Potemski
authors.affiliation: ∇National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan.
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: ∇National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044 Japan.
authors.forename: T
authors.initials: T
authors.lastname: Taniguchi
authors.forename: S J
authors.initials: SJ
authors.lastname: Haigh
authors.forename: A K
authors.initials: AK
authors.lastname: Geim
authors.forename: R V
authors.initials: RV
authors.lastname: Gorbachev
keywords: Phosphorene; electronic transport; field effect; niobium diselenide; superconductivity; transition metal dichalcogenides