2020/08/31 by Xiaoyu Zhang, Ayhan Duzgun, Yuyang Lao +16
Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Ferromagnetism #Frustration #Magnetic field #Magnetic monopole #Magnetic properties of thin films #Nanomagnet #Phase transition #Physics #Quantum mechanics #Spin ice #String (physics) #Theoretical and Computational Physics #Theoretical physics #cond-mat.mes-hall
paper · pdf · doi:10.1038/s41467-021-26734-6
46 pages including SI
arxiv created 2021/10/20 · openalex publication_date 2021/11/11 · arxiv updated 2021/11/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
One-dimensional strings of local excitations are a fascinating feature of the physical behavior of strongly correlated topological quantum matter. Here we study strings of local excitations in a classical system of interacting nanomagnets, the Santa Fe Ice geometry of artificial spin ice. We measured the moment configuration of the nanomagnets, both after annealing near the ferromagnetic Curie point and in a thermally dynamic state. While the Santa Fe Ice lattice structure is complex, we demonstrate that its disordered magnetic state is naturally described within a framework of emergent strings. We show experimentally that the string length follows a simple Boltzmann distribution with an energy scale that is associated with the system's magnetic interactions and is consistent with theoretical predictions. The results demonstrate that string descriptions and associated topological characteristics are not unique to quantum models but can also provide a simplifying description of complex classical systems with non-trivial frustration.