Quantum Metamaterials from Block Copolymer Nanocomposites: Synthetic Pathways to Mesostructured Carbonitride Superconductors

In recent decades, block copolymer (BCP)-inorganic nanocomposite co-assembly has emerged as a highly tunable route to the synthesis of crystallographically ordered, mesoporous inorganic materials. These materials have found numerous applications in catalysis, energy conversion and storage, and other areas. One notable area in which BCP-directed assembly has made few inroads, however, is the production of electronic-grade materials suitable for studies of emergent phenomena, i.e. quantum metamaterials. For example, superconductors with mesoscale ordering are expected to have properties different from their bulk counterparts. The exploration of these properties has been limited by the lack of tunable, robust synthesis methodologies. We have developed a route to gyroidal NbN superconductors from poly(isoprene-b-styrene-b-ethylene oxide)-Nb₂O₅ nanocompositesusing high-temperature annealing in ammonia gas. In recent work, we have developed synthesis routes using methane gas that enable the synthesis of carbonitrides with superconductor quality comparable to bulk samples and tunable morphology across the BCP phase diagram. These morphologies exhibit differences in the transition onset and magnetization behavior, potentially the first hallmarks of quantum metamaterial behavior.