Epitaxial interfaces between magnetic pyrochlores: Enable exotic topological and electronic states

Interfaces between dissimilar magnetic pyrochlore crystals hold great potential for discovering new interfacial phenomena because of the strong interactions between these phases. However, creating such interfaces has been significantly limited by current material synthesis methods. Recently, we devised a new synthesis technique that enables the previously unexplored magnetic pyrochlore interface between the spin ice Dy₂Ti₂O₇and the magnetic Weyl semimetal Eu₂Ir₂O₇. This method uses an ultra-high supersaturation during deposition followed by rapid quench, which results in a metallic glass state. Next, the application of directional IR-laser-driven thermal gradients during post-annealing converts amorphous covalent networks into nearly perfectly ordered, atomically and chemically sharp interfaces. The new magnetic pyrochlore interface opens opportunities to investigate interactions between relativistic Weyl fermions and magnetic monopoles in spin ice, including quantum spin ices (e.g., Tb₂Ti₂O₇).