  In recent years, the notion of Quantum Materials has emerged as a powerful
unifying concept across diverse fields of science and engineering, from
condensed-matter and cold atom physics to materials science and quantum
computing. Beyond traditional quantum materials such as unconventional
superconductors, heavy fermions, and multiferroics, the field has significantly
expanded to encompass topological quantum matter, two-dimensional materials and
their van der Waals heterostructures, Moire materials, Floquet time crystals,
as well as materials and devices for quantum computation with Majorana
fermions. In this Roadmap collection we aim to capture a snapshot of the most
recent developments in the field, and to identify outstanding challenges and
emerging opportunities. The format of the Roadmap, whereby experts in each
discipline share their viewpoint and articulate their vision for quantum
materials, reflects the dynamic and multifaceted nature of this research area,
and is meant to encourage exchanges and discussions across traditional
disciplinary boundaries. It is our hope that this collective vision will
contribute to sparking new fascinating questions and activities at the
intersection of materials science, condensed matter physics, device
engineering, and quantum information, and to shaping a clearer landscape of
quantum materials science as a new frontier of interdisciplinary scientific
inquiry.
