Disorder-independent control of magnetic monopole defect population in artificial spin-ice honeycombs

Ladak, Sam; Walton, S. K.; Zeissler, Katharina; Tyliszczak, Tolek; Read, Dan; Branford, W. R.; Cohen, L. F.

doi:10.1088/1367-2630/14/4/045010

Cited by 24 publications

(31 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar type of selectivity was recently observed in cross-shaped nanowire vertices21. The magnetic domain wall type and structure depends on the bar dimensions; in the permalloy artificial spin ice studied in this publication, transverse domain walls are supported22. In this study we discuss the effect of the chirality of transverse domain walls on the propagation direction chosen at each vertex in a 180° reversal scenario.…”

supporting

confidence: 73%

See 1 more Smart Citation

The non-random walk of chiral magnetic charge carriers in artificial spin ice

Zeissler

Walton

Ladak

et al. 2013

Sci Rep

View full text Add to dashboard Cite

The flow of magnetic charge carriers (dubbed magnetic monopoles) through frustrated spin ice lattices, governed simply by Coulombic forces, represents a new direction in electromagnetism. Artificial spin ice nanoarrays realise this effect at room temperature, where the magnetic charge is carried by domain walls. Control of domain wall path is one important element of utilizing this new medium. By imaging the transit of domain walls across different connected 2D honeycomb structures we contribute an important aspect which will enable that control to be realized. Although apparently equivalent paths are presented to a domain wall as it approaches a Y-shaped vertex from a bar parallel to the field, we observe a stark non-random path distribution, which we attribute to the chirality of the magnetic charges. These observations are supported by detailed statistical modelling and micromagnetic simulations. The identification of chiral control to magnetic charge path selectivity invites analogy with spintronics.

show abstract

supporting

confidence: 73%

“…Micromagnetic simulations were performed on the field-driven transit of a domain wall through a single vertex at 0 K using the OOMMF software22. In the simulation perfect selectivity was observed in the transverse domain wall regime.…”

Section: Resultsmentioning

confidence: 99%

The non-random walk of chiral magnetic charge carriers in artificial spin ice

Zeissler

Walton

Ladak

et al. 2013

Sci Rep

View full text Add to dashboard Cite

show abstract

“…However, the ice rule can be broken on application of a magnetic field [21,29], leading to a regular array of ice rule defects at low dipolar coupling [30,31]. It should also be pointed out that, while arrangements of dipolar coupled nanomagnets are thought to be a good way to mimic the behaviour of Ising spins, one can also consider systems made up of connected nanowires that, for example, form a honeycomb network with the artificial kagome spin ice geometry [19,21,[32][33][34]. In the connected systems, the fundamental reversal processes are different from those of the individual nanomagnets.…”

Section: From Water Ice To Artificial Spin Icementioning

confidence: 99%

Artificial ferroic systems: novel functionality from structure, interactions and dynamics

Heyderman¹,

Stamps²

2013

J. Phys.: Condens. Matter

211

193

View full text Add to dashboard Cite

Lithographic processing and film growth technologies are continuing to advance, so that it is now possible to create patterned ferroic materials consisting of arrays of sub-1 μm elements with high definition. Some of the most fascinating behaviour of these arrays can be realised by exploiting interactions between the individual elements to create new functionality. The properties of these artificial ferroic systems differ strikingly from those of their constituent components, with novel emergent behaviour arising from the collective dynamics of the interacting elements, which are arranged in specific designs and can be activated by applying magnetic or electric fields. We first focus on artificial spin systems consisting of arrays of dipolar-coupled nanomagnets and, in particular, review the field of artificial spin ice, which demonstrates a wide range of fascinating phenomena arising from the frustration inherent in particular arrangements of nanomagnets, including emergent magnetic monopoles, domains of ordered macrospins, and novel avalanche behaviour. We outline how demagnetisation protocols have been employed as an effective thermal anneal in an attempt to reach the ground state, comment on phenomena that arise in thermally activated systems and discuss strategies for selectively generating specific configurations using applied magnetic fields. We then move on from slow field and temperature driven dynamics to high frequency phenomena, discussing spinwave excitations in the context of magnonic crystals constructed from arrays of patterned magnetic elements. At high frequencies, these arrays are studied in terms of potential applications including magnetic logic, linear and non-linear microwave optics, and fast, efficient switching, and we consider the possibility to create tunable magnonic crystals with artificial spin ice. Finally, we discuss how functional ferroic composites can be incorporated to realise magnetoelectric effects. Specifically, we discuss artificial multiferroics (or multiferroic composites), which hold promise for new applications that involve electric field control of magnetism, or electric and magnetic field responsive devices for high frequency integrated circuit design in microwave and terahertz signal processing. We close with comments on how enhanced functionality can be realised through engineering of nanostructures with interacting ferroic components, creating opportunities for novel spin electronic devices that, for example, make use of the transport of magnetic charges, thermally activated elements, and reprogrammable nanomagnet systems.

show abstract

“…The shape anisotropy of each nanobar forces its magnetization to lie in one of two directions along its long axis and so it acts as an 'ising macrospin'. The term ASI was originally applied to a square array of electrically and magnetically isolated bars [3], but here we consider continuous honeycomb or kagome ASI structures [4][5][6][7][8][9][10][11][12][13][14][15][16]. In the honeycomb three of these ising macrospins meet at each vertex and their interactions are governed by a set of 'ice rules', which minimize the local magnetic charge at each vertex without favouring a specific spin structure.…”

Section: Introductionmentioning

confidence: 99%

Limitations in artificial spin ice path selectivity: the challenges beyond topological control

et al. 2015

Self Cite

View full text Add to dashboard Cite

Magnetic charge is carried through nanowire networks by domain walls, and the micromagnetic structure of a domain wall provides an opportunity to manipulate its movement. We have shown previously that magnetic monopole defects exist in artificial spin ice (ASI) and result from two bar switching at a vertex. To create and manipulate monopole defects and indeed magnetic charge in general, path selectivity of the domain wall at a vertex is required. We have recently shown that in connected ASI structures, transverse wall chirality (or topology) determines wall path direction, but a mechanism known as Walker breakdown, where a wall mutates into a wall of opposite chirality partially destroys selectivity. Recently it has been claimed that in isolated Y-shaped junctions that support vortex walls, selectivity is entirely determined by chirality (or topology), the suggestion being that vortex wall chirality is robust in the Walker breakdown process. Here we demonstrate that in Yshaped junctions, magnetic switching in the important topologically protected regime exists only for a narrow window of field and bar geometry, and that it will be challenging to access this regime in fielddriven ASI. This work has implications for the wider field of magnetic charge manipulation for high density memory storage.

show abstract

Disorder-independent control of magnetic monopole defect population in artificial spin-ice honeycombs

Cited by 24 publications

References 14 publications

The non-random walk of chiral magnetic charge carriers in artificial spin ice

The non-random walk of chiral magnetic charge carriers in artificial spin ice

Artificial ferroic systems: novel functionality from structure, interactions and dynamics

Limitations in artificial spin ice path selectivity: the challenges beyond topological control

Contact Info

Product

Resources

About