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arXiv · 2005.00461

Epitaxial engineering of flat silver fluorides cuprate analogs

Abstract

As-grown AgF2 has a remarkably similar electronic structure as insulating cuprates, but it is extremely electronegative, which makes it hard to handle and dope. Furthermore, buckling of layers reduces magnetic interactions and enhances unwanted self-trapping lattice effects. We argue that epitaxial engineering can solve all these problems. By using a high throughput approach and first principle computations, we find a set of candidate substrates which can sustain the chemical aggressiveness of AgF2 and at the same time have good lattice parameter matching for heteroepitaxy, enhancing AgF2 magnetic and transport properties and opening the possibility of field-effect carrier injection to achieve a new generation of high-Tc superconductors. Assuming a magnetic mechanism and extrapolating from cuprates we predict that the superconducting critical temperature of a single layer can reach 195 K.

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Adam Grzelak, Haibin Su, Xiaoping Yang, Dominik Kurzydłowski, Jose Lorenzana, Wojciech Grochala. 2020-05-01. Epitaxial engineering of flat silver fluorides cuprate analogs. https://doi.org/10.1103/physrevmaterials.4.084405

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