Freestanding infinite-layer nickelate membranes

Five years since the discovery of superconducting infinite-layer nickelate thin films, a superconducting bulk counterpart remains elusive. On the other hand, the synergy of refined synthesis techniques and compressive epitaxial strain geometry has continued to lift the upper bound on the superconducting transition temperature^1,2. A natural question is then to what extent strain gives rise to superconductivity in infinite-layer nickelates. Through epitaxial strain engineering, achieving uniform control over varying levels of disorder across different samples remains challenging. To this end, we have fabricated freestanding infinite-layer nickelate membranes with comparable structural, transport, and superconducting properties as those of optimized thin films³. We will discuss our approach towards probing and manipulating superconducting properties in infinite-layer nickelates without the limitation of substrate constraints.

1. K. Lee et al., Nature 619, 288-292 (2023).

2. L. E. Chow et al., arXiv: 2410.00144 (2024).

3. Y. Lee et al. arXiv: 2402.05104 (2024).