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11 Jan 21:23

Electromechanical control of nitrogen-vacancy defect emission using graphene NEMS

by Antoine Reserbat-Plantey

Article

Active control of optical fields at the nanoscale is difficult to achieve. Here, the authors fabricate an on-chip graphene NEMS suspended a few tens of nanometres above nitrogen vacancy centres and demonstrate electromechanical control of the photons emitted by electrostatic tuning of the graphene NEMS position.

Nature Communications doi: 10.1038/ncomms10218

Authors: Antoine Reserbat-Plantey, Kevin G. Sch├Ądler, Louis Gaudreau, Gabriele Navickaite, Johannes G├╝ttinger, Darrick Chang, Costanza Toninelli, Adrian Bachtold, Frank H. L. Koppens

27 May 16:04

Superelastic Organic Crystals

by Satoshi Takamizawa, Yasuhiro Miyamoto

Abstract

Superelastic materials (crystal-to-crystal transformation pseudo elasticity) that consist of organic components have not been observed since superelasticity was discovered in a Au-Cd alloy in 1932. Superelastic materials have been exclusively developed in metallic or inorganic covalent solids, as represented by Ti-Ni alloys. Organosuperelasticity is now revealed in a pure organic crystal of terephthalamide, which precisely produces a large motion with high repetition and high energy storage efficiency. This process is driven by a small shear stress owing to the low density of strain energy related to the low lattice energy.

Thumbnail image of graphical abstract

A pure organic crystal of terephthalamide exhibits superelasticity (crystal-to-crystal transformation pseudo elasticity). A large motion is produced precisely with high repetition and high energy storage efficiency. This process is driven by a small shear stress owing to the low density of strain energy, which is related to the low lattice energy.