Thickness dependence of the twin density in YBa2Cu3O7−δ thin films sputtered onto MgO substrates

Abstract

The lengths and spacings of twins in YBa2Cu3O7−δ thin films deposited onto MgO substrates have been measured by transmission electron microscopy as a function of film thickness t, for t ranging from 50 to 1400 nm. The twin length is linear in t, while the twin spacing follows a t1/2 dependence. This form for the twin spacing is consistent with the prediction of a simple free energy expression for the twinning transformation.

Modeling flux pinning in thin undoped and BaZrO3-doped YBCO films

“…The twin width distribution is even harder to tune than the dislocation density; the mean twin width depends on material parameters, such as twin boundary energy, film-substrate interface stress, and the elastic modulus. 3 The only parameter that can be affected in deposition is the elastic modulus, which increases with higher concentration of crystalline defects, e.g., dislocations.…”

“…The whole film is covered by twin domains which are a few micrometers long and wide and a single domain is filled by individual twin boundaries with spacing of about 20-30 nm. 3,4 The twin planes are oriented evenly in ͑110͒ and ͑110͒ directions 5 in films on cubic substrates. The twins are pinning sites for transversal vortex motion and channel vortices along the plane.…”

First-principles calculations of the twin boundary energies and adhesion energies of interfaces for cubic face-centered transition-metal nitrides and carbides

“…By means of sputter deposition, nanoscale twins can be produced in various materials at high deposition rates [15,19,20]. When deposited on a substrate such as Si, MgO or steel, thin films are grown with columnar grains, in which coherent twin boundaries evolve paralles to the surface.…”

Electron Beam Induced Light Emission and Charge Conduction Patterning in ZnO by Using an AlOx Layer

“…[3] In addition to lighting and display applications, when it is doped with group III elements, ZnO can have a carrier concentration as high as 10 20 cm ±3 , while at the same time remaining optically transparent. [4] These properties, together with the newly discovered property of room-temperature ferromagnetism, [5] are why ZnO-based semiconductors are currently being considered as potential candidates for various novel devices, such as nanowire lasers, [6] random lasers, [7] invisible circuits, [8] and spintronic devices. [5] In the realm of nanotechnology, acquiring the know-how to control the local properties of materials, particularly on a length scale of nanometers, is of great interest, both scientifically and technologically, because it offers the advantage of easily fabricating functional devices on the same material.…”