title: Auxetic and Ferroelastic Borophane: A Novel 2D Material with Negative Possion's Ratio and Switchable Dirac Transport Channels.
abstract: Recently synthesized atomically thin boron sheets (that is, borophene) provide a fascinating template for new material property discovery. Here, we report findings of an extraordinary combination of unusual mechanical and electronic properties in hydrogenated borophene, known as borophane, from first-principles calculations. This novel 2D material has been shown to exhibit robust Dirac transport physics. Our study unveils that borophane is auxetic with a surprising negative Poisson's ratio stemming from its unique puckered triangle hinge structure and the associated hinge dihedral angle variation under a tensile strain in the armchair direction. Our results also identify borophane to be ferroelastic with a stress-driven 90° lattice rotation in the boron layer, accompanied by a remarkable orientation switch of the anisotropic Dirac transport channels. These outstanding strain-engineered properties make borophane a highly versatile and promising 2D material for innovative applications in microelectromechanical and nanoelectronic devices.
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology , Garden Point Campus, QLD 4001, Brisbane, Australia.|Integrated Materials Design Centre (IMDC), School of Chemical Engineering, University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Liangzhi
authors.initials: L
authors.lastname: Kou
authors.affiliation: Department of Physics and Earth Science, Jacobs University Bremen , Campus Ring 1, 28759 Bremen, Germany.
authors.forename: Yandong
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Physics and Astronomy and High Pressure Science and Engineering Center, University of Nevada , Las Vegas, Nevada 89154, United States.
authors.forename: Chun
authors.initials: C
authors.lastname: Tang
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology , Garden Point Campus, QLD 4001, Brisbane, Australia.
authors.forename: Ziqi
authors.initials: Z
authors.lastname: Sun
authors.affiliation: School of Chemistry, Physics and Mechanical Engineering Faculty, Queensland University of Technology , Garden Point Campus, QLD 4001, Brisbane, Australia.
authors.forename: Aijun
authors.initials: A
authors.lastname: Du
authors.affiliation: Department of Physics and Astronomy and High Pressure Science and Engineering Center, University of Nevada , Las Vegas, Nevada 89154, United States.
authors.forename: Changfeng
authors.initials: C
authors.lastname: Chen
keywords: Borophane; auxeticity; ferroelasticity; switchable Dirac transport channels