title: Torsional stick-slip behavior in WS2 nanotubes.
abstract: We experimentally observed atomic-scale torsional stick-slip behavior in individual nanotubes of tungsten disulfide (WS2). When an external torque is applied to a WS2 nanotube, all its walls initially stick and twist together, until a critical torsion angle, at which the outer wall slips and twists around the inner walls, further undergoing a series of stick-slip torque oscillations. We present a theoretical model based on density-functional-based tight-binding calculations, which explains the torsional stick-slip behavior in terms of a competition between the effects of the in-plane shear stiffness of the WS2 walls and the interwall friction arising from the atomic corrugation of the interaction between adjacent WS2 walls.
authors.affiliation: Department of Materials and Interfaces, Weizmann Institute of Science, Rehovot 76100, Israel. nagapriya.kavoori@weizmann.ac.il
authors.forename: K S
authors.initials: KS
authors.lastname: Nagapriya
authors.forename: Ohad
authors.initials: O
authors.lastname: Goldbart
authors.forename: Ifat
authors.initials: I
authors.lastname: Kaplan-Ashiri
authors.forename: Gotthard
authors.initials: G
authors.lastname: Seifert
authors.forename: Reshef
authors.initials: R
authors.lastname: Tenne
authors.forename: Ernesto
authors.initials: E
authors.lastname: Joselevich