Nature doesn't like having interfaces—this is why bubbles like to be round, and the surface of a pond settles to flat as long as it's not disturbed. These trends minimize the total amount of interface (or surface) that is present. As an exception to this behavior, certain materials are known to have a property, called negative stiffness, where the interface prefers to become distorted, or wavy, even without any external stimulation. Interfaces with negative stiffness have been considered in crystals before, but the characteristic has now also been found in modern magnetism.
Magnetization of nanoscale magnets by ultrashort electron pulses and chiral Majorana fermion modes
Observation and measurement of ultra-fast vortex dynamics in superconductors, how to identify new examples of topological materials, ultracold chemical reaction, and manipulating electron spins without loss of information
New quantum phase with atomic magnets quantum-entangled in sets of four, fluorinated h-BN as a magnetic semiconductor, and electrical generation of exciton-polaritons
New understanding of quantum cooling, "fooling" Heisenberg's uncertainty principle, wave nature of light in super-slow motion, and towards classically driven blind quantum computation
Control of thermal and electrical currents by quantum observation, quantum oscillations in graphene, controlling and measuring electron spin voltage, and a multispecies trapped-ion node for quantum networking