Switchable geometric frustration in an artificial-spin-ice–superconductor heterosystem

Journal Article · Mon Jun 11 00:00:00 EDT 2018 · Nature Nanotechnology

DOI:https://doi.org/10.1038/s41565-018-0162-7· OSTI ID:1466321

Wang, Yong-Lei ; Ma, Xiaoyu; Xu, Jing; Xiao, Zhi-Li; Snezhko, Alexey; Divan, Ralu; Ocola, Leonidas E.; Pearson, John E.; Janko, Boldizsar; Kwok, Wai-Kwong

Geometric frustration emerges when local interaction energies in an ordered lattice structure cannot be simultaneously minimized, resulting in a large number of degenerate states. The numerous degenerate configurations may lead to practical applications in microelectronics(1), such as data storage, memory and logic(2). However, it is difficult to achieve very high degeneracy, especially in a two-dimensional system(3,4). Here, we showcase in situ controllable geometric frustration with high degeneracy in a two-dimensional flux-quantum system. We create this in a superconducting thin film placed underneath a reconfigurable artificial-spin-ice structure(5). The tunable magnetic charges in the artificial-spin-ice strongly interact with the flux quanta in the superconductor, enabling switching between frustrated and crystallized flux quanta states. The different states have measurable effects on the superconducting critical current profile, which can be reconfigured by precise selection of the spin-ice magnetic state through the application of an external magnetic field. We demonstrate the applicability of these effects by realizing a reprogrammable flux quanta diode. The tailoring of the energy landscape of interacting 'particles' using artificial-spin-ices provides a new paradigm for the design of geometric frustration, which could illuminate a path to control new functionalities in other material systems, such as magnetic skyrmions(6), electrons and holes in two-dimensional materials(7,8), and topological insulators(9), as well as colloids in soft materials(10-13).

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: USDOE Office of Science - Office of Basic Energy Sciences - Materials Sciences and Engineering Division; USDOE Office of Science - Office of Basic Energy Sciences - Scientific User Facilities Division; National Science Foundation (NSF)
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1466321
• Journal Information: Nature Nanotechnology, Vol. 13, Issue 7; ISSN 1748-3387
• Publisher: Nature Publishing Group
• Country of Publication: United States
• Language: English