Quantum Materials at Surfaces and Interfaces-Emergent Phenomena and Insights From the Special Section.

The study of matter at the quantum scale continues to reshape the understanding of condensed matter physics and materials science. Over the past two decades, quantum phenomena in surfaces and interfaces at the atomic scale have emerged as a unifying theme that connects diverse research efforts ranging from topological phases to two-dimenssional (2D) crystals and strongly correlated electron systems. What distinguishes this field is not only the discovery of new phases of matter, but also the recognition that surfaces and interfaces are natural platforms where quantum effects are amplified, stabilized, or even newly created. The control of quantum states at these reduced dimensions is rapidly becoming central to both fundamental research and future device applications. The articles collected in this special section reflect the richness of current research associated with the 15th International Conference on Atomically Controlled Surfaces, Interfaces and Nanostructures (ACSIN-15) held in Suzhou, China.