Field-Tunable Interactions and Frustration in Underlayer-Mediated Artificial Spin Ice
- Pennsylvania State Univ., University Park, PA (United States); North Central College, Naperville, IL (United States)
- Pennsylvania State Univ., University Park, PA (United States)
- Univ. of Kassel (Germany)
- Univ. of Illinois at Urbana-Champaign, IL (United States)
- Yale Univ., New Haven, CT (United States)
We report that artificial spin ice systems have opened experimental windows into a range of model magnetic systems through the control of interactions among nanomagnet moments. This control has previously been enabled by altering the nanomagnet size and the geometry of their placement. Here we demonstrate that the interactions in artificial spin ice can be further controlled by including a soft ferromagnetic underlayer below the moments. Such a substrate also breaks the symmetry in the array when magnetized, introducing a directional component to the correlations. Using spatially resolved magneto-optical Kerr effect microscopy to image the demagnetized ground states, we show that the correlation of the demagnetized states depends on the direction of the underlayer magnetization. Further, the relative interaction strength of nearest and next-nearest neighbors varies significantly with the array geometry. We exploit this feature to induce frustration in an inherently unfrustrated square lattice geometry, demonstrating new possibilities for effective geometries in two-dimensional nanomagnetic systems.
- Research Organization:
- Univ. of Illinois at Urbana-Champaign, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States); Yale Univ., New Haven, CT (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
- Grant/Contract Number:
- SC0010778; AC02-06CH11357; SC0020162; DMR-1420620
- OSTI ID:
- 1851434
- Journal Information:
- Physical Review Letters, Vol. 127, Issue 11; ISSN 0031-9007
- Publisher:
- American Physical Society (APS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
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