# Discovery of Giant Unit-Cell Super-Structure in the Infinite-Layer Nickelate PrNiO$\_2$

Source: [Discovery of Giant Unit-Cell Super-Structure in the Infinite-Layer Nickelate PrNiO$\_2$](<https://www.sota2.com/research/paper/68fa490a1e209131ce934250>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-25T07:08:35.105Z

Authors: J. Oppliger, J. K\\"uspert, A.-C. Dippel, M. v. Zimmermann, O. Gutowski, X. Ren, X. J. Zhou, Z. Zhu, R. Frison, Q. Wang, L. Martinelli, I. Bia{\\l}o, J. Chang

Published: 2024-04-27T06:29:46.000Z

## Abstract

Spectacular quantum phenomena such as superconductivity often emerge in flat-band systems where Coulomb interactions overpower electron kinetics. Engineering strategies for flat-band physics is therefore of great importance. Here, using high-energy grazing-incidence x-ray diffraction, we demonstrate how in-situ temperature annealing of the infinite-layer nickelate PrNiO$\_2$ induces a giant superlattice structure. The annealing effect has a maximum well above room temperature. By covering a large scattering volume, we show a rare period-six in-plane (bi-axial) symmetry and a period-four symmetry in the out-of-plane direction. This giant unit-cell superstructure likely stems from ordering of diffusive oxygen. The stability of this superlattice structure suggests a connection to an energetically favorable electronic state of matter. As such, our study provides a new pathway - different from Moir\\'e structures - to ultra-small Brillouin zone electronics.

## Recorded benchmark results

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## Original sources and implementation

[Original paper](<https://arxiv.org/abs/2404.17795>)

[PDF](<https://arxiv.org/pdf/2404.17795.pdf>)