Artificial spin ice systems are two-dimensional arrays of interacting ferromagnetic nanoislands with uniaxial single-domain magnetization. By carefully designing the geometry of these arrays, some systems show collective phenomena associated with emergent higher-order frustration. Here we report a study on the Santa Fe Ice (SFI) system, which has an intrinsic population of excited vertices built into the geometry. Its magnetic configuration can be represented via emergent “strings” that connect all excited vertices, and thus moment fluctuations can be understood through the strings’ kinetics. SFI is predicted to have either a disordered ground state or a long-range ordered ground state associated with the distribution of excited vertices, depending on the local interactions. We have performed a magnetic force microscopy study on SFI after annealing near the Curie temperature and photoemission electron microscopy (PEEM) measurements on thermally active SFI. Our results indicate that SFI represents an unusual instance of emergent topological complexity.
*This work is funded by the US Department of Energy, Office of Basic Energy Sciences. Work at the University of Minnesota, University of Liverpool, and LANL are sponsored by NSF, the UK Royal Society and the US DoE, respectively.
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Presenters
Xiaoyu Zhang
Department of Applied Physics, Yale University
Yale University
Authors
Xiaoyu Zhang
Department of Applied Physics, Yale University
Yale University
Ayhan Duzgun
Los Alamos National Laboratory
Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory
Yuyang Lao
Department of Physics, University of Illinois at Urbana-Champaign
University of Illinois at Urbana-Champaign
Nicholas Bingham
Department of Applied Physics, Yale University
Yale University
Joseph N Sklenar
Wayne State University
Department of Physics and Astronomy, Wayne State University
Physics and Astronomy, Wayne State University
Hilal Saglam
Materials Science Division, Argonne National Laboratory
Applied Physics, Yale University
Department of Applied Physics, Yale University
Yale University
Rajesh Chopdekar
Lawrence Berkeley National Lab
Lawrence Berkeley Natl Lab
Advanced Light Source, Lawrence Berkeley National Laboratory
Lawrence Berkeley National Laboratory
Advance Light Source, Lawrence Berkeley National Laboratory
Shayaan Subzwari
Yale University
Joseph Batley
School of Physics and Astronomy, University of Minnesota
University of Minnesota
Justin Watts
School of Physics and Astronomy, University of Minnesota
University of Minnesota
Daniel Bromley
University of Liverpool, Liverpool
Chris Leighton
University of Minnesota
Chemical Engineering and Materials Science, University of Minnesota
Department of Chemical Engineering and Materials Science, University of Minnesota
Liam O'Brien
University of Liverpool, Liverpool
Cristiano Nisoli
Theoretical Division, Los Alamos National Laboratory
Los Alamos National Lab
Los Alamos Natl Lab
Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory
Los Alamos National Laboratory
Peter Schiffer
Yale University
Department of Applied Physics, Yale University
Department of Applied Physics and Department of Physics, Yale University
