We demonstrate the successful fabrication and transport characterization of free-standing, electron-doped cuprate heterostructures with thicknesses down to 10 nm.

By removing the constraints of a growth substrate, we create a platform where the lattice can be continuously and significantly deformed. Transmission Electron Microscopy (TEM) confirms that these membranes maintain the crystalline coherence characteristic of epitaxial thin films. Electrical transport measurements reveal a sharp superconducting transition. We find that the transition temperature is sensitive to external strain.

We analyze these shifts within the context of the interplay between superconductivity and antiferromagnetism. Our results highlight the potential of free-standing membranes as a powerful tool for "strain-engineering" the phase diagrams of strongly correlated electron systems and superconductors.