A route to discover novel quantum states: The recent experimental advancements of pyrochlore iridate thin films

The lattice of pyrochlore iridate compounds consists of interpenetrating corner-sharing tetrahedra of rare-earth elements and Ir ions. Owing to the geometrically frustrated structure, pyrochlore iridates are considered as a cradle of novel quantum phenomena and attracting much attention in condensed matter physics and materials science. Here, we present a brief review of the advancements in the preparation methods of pyrochlore iridate crystals. Moreover, due to the controllable high crystallinity with a bunch of physical advantages, we introduce the recent discoveries of exotic correlated and topological phases in pyrochlore iridate thin films. For this rapidly developing field, this review provides perspectives on current challenges and opportunities aiming to expand future research.