Real-space orbital tiling approach for the design of novel superconductors

TL;DR

This paper introduces a real-space orbital tiling framework, ROSP, for designing new superconductors by focusing on atomic orbital configurations rather than traditional structure or electron count, enabling targeted discovery of high-Tc materials.

Contribution

The paper proposes the ROSP model that links orbital tilings to superconductivity, offering a novel approach for materials design based on real-space orbital architecture.

Findings

ROSP explains superconductivity in La-based compounds despite structural differences.

Orbital tilings can classify superconductor families beyond structure or electron count.

New superconductor families are proposed on the anti-cuprate lattice.

Abstract

Despite substantial advances in the field, we still lack a predictive framework capable of guiding the discovery of new families of superconductors. While momentum-space approaches have advanced the microscopic understanding of superconductivity, they offer limited guidance for materials design based on atomic building blocks. Here, we propose a real-space framework which conceptualizes Cooper pairs as confined standing waves resulting from coherent tilings of atomic orbitals. We call this model the Real-space Orbital Superconducting Pathway (ROSP). Using a tight-binding toy model, we show that the energetics of electron pairing depend on the configuration and overlap of real-space orbitals, which motivates \textit{a priori} design of superconducting families from orbital tiling. We connect the ROSP model to Roald Hoffmann's isolobal analogy to classify families of superconductors based on shared orbital tilings, rather than structure or electron count. As an example, we suggest that superconductivity in La$_{3}$Ni$_{2}$O$_{7}$ and LaNiO$_{2}$, despite differing structures and electron counts, may arise from a common ROSP. We introduce a new notation to classify two-dimensional square-net ROSPs and further propose several new families of superconductors on the anti-cuprate lattice. This framework provides a new model for predicting and designing families of high-T$_c$ superconductors from real-space orbital architecture, even without microscopic knowledge of the attractive pairing interaction.