Imaging the structure of the interface between symmetries interconnected by a discontinuous transition

doi:10.1016/S0038-1098(03)00645-8

Solid State Communications

Volume 128, Issues 2–3, October 2003, Pages 51-56

https://doi.org/10.1016/S0038-1098(03)00645-8 Get rights and content

Abstract

We have been able to observe with single particle resolution the interface between two structural symmetries that cannot be interconnected by a continuous transition. By means of an engineered 2D potential that pins the extremity of vortex strings a square symmetry was imposed at the surface of a 3D vortex solid. Using the Bitter decoration technique and on account of the continuous vortex symmetry, we visualize how the induced structure transforms along the vortex direction before changing into the expected hexagonal structure at a finite distance from the surface.

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Acknowledgements

We acknowledge A.A. Aligia, J. Lorenzana, C. Balseiro, E. Jagla, P. Cornaglia and F. Laguna for valuable discussions and E. Martı́nez for careful reading of the manuscript. This work was partially supported by Agencia Nacional de Promoción Cientı́fica y Tecnológica, by Fundación Antorchas and by Consejo Nacional de Investigaciones Cientı́ficas y Técnicas, Argentina.

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Citation Excerpt :
The behavior of a collection of particles in two dimensions in the presence of a periodic substrate potential has been of interest in the context of various types of systems. These include vortices in superconductors [1–7], modeling of friction with solid on solid models [8–11], and also experimental set ups involving colloidal aggregates in the presence of a substrate potential created by interfering laser beams [12–14]. The periodic substrate potential could differ in symmetry, strength of the pinning potential (in relation to the inter-particle interaction), range of the pinning potential and density of pins.
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¹: Permanent address: Unitá INFM e Dipartimento di Fisica, Universitá di Roma Tre, Rome, Italy.

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Imaging the structure of the interface between symmetries interconnected by a discontinuous transition

Abstract

Section snippets

Acknowledgements

Statistical Physics

Principles of Condensed Matter Physics

Phys. Rev. Lett.

Phys. Rev. Lett.

Nature

Phys. Rev. B

Phys. Rev. Lett.