Disorder Drives Long-Range Order in “Tetris Ice” Nanomagnet Arrays

Disorder Drives Long-Range Order in “Tetris Ice” Nanomagnet Arrays: Long-range ordering is typically associated with a decrease in disorder, or entropy. Yet, it can also be driven by increasing entropy in certain special cases. In a recent DOE-funded study, researchers demonstrated that certain artificial spin-ice arrays—nanomagnets lithographically patterned to form Tetris-like shapes—can produce such entropy-driven order.