Atomic-Scale Insights into Doping-Tuned High-Pressure Nickelate Superconductors

• Applicant: Dr. Yusuf Eren Suyolcu
• Subject Area: Synthesis and Properties of Functional Materials
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 570575068

Quantum materials hold a significant role in condensed matter physics and are anticipated to drive the forthcoming surge of technological progress. One of the most prominent examples is superconductors, which have been widely studied in copper-oxide compounds (cuprates), in the last decades. The recent discovery of high-temperature superconductivity in a nickel-oxide compound (nickelate), La₃Ni₂O₇, at high-pressures exceeding 14 GPa has sparked significant research interest. Yet, the intrinsic properties of this phase remain under intense debate—particularly regarding its potential filamentary character—and understanding the atomic-scale mechanisms underpinning these phenomena remains critical. This project aims to uncover the fundamental mechanisms behind superconductivity in a new class of layered nickel-based materials, known as Ruddlesden-Popper (RP) nickelates. These materials have recently shown promising signs of becoming high-temperature superconductors, especially under high pressure. By creating and studying high-quality crystals—both undoped and electron-doped—at the atomic level, the project seeks to understand how their internal structure affects their superconducting behavior. Using advanced scanning transmission electron microscopy at both room and cryogenic temperatures, the research will explore how local structural changes and electronic interactions are linked to the emergence of superconductivity. The findings could lead to new ways of designing materials with improved superconducting properties.

• DFG Programme: Research Grants