Thermal excitations within and among mesospins in artificial spin ice

Texture fluctuations and emergent dynamics in coupled nanomagnets

“…However, dynamic edge modes may occur at frequencies inside to the band gap. We have previously confirmed the existence of additional modes [17,19], associated with a binary stochastic fluctuation of the magnetization at the edges, from hereon called edge fluctuations. These edge fluctuations cause switching between S-or C-states [20], and their presence results in a residual entropy in magnetic metamaterials [17,21].…”

“…We have previously confirmed the existence of additional modes [17,19], associated with a binary stochastic fluctuation of the magnetization at the edges, from hereon called edge fluctuations. These edge fluctuations cause switching between S-or C-states [20], and their presence results in a residual entropy in magnetic metamaterials [17,21]. They have recently also been confirmed experimentally, and were found to occur at shorter time-and length-scales than conventional mesospin switching [17].…”

“…These edge fluctuations cause switching between S-or C-states [20], and their presence results in a residual entropy in magnetic metamaterials [17,21]. They have recently also been confirmed experimentally, and were found to occur at shorter time-and length-scales than conventional mesospin switching [17]. Thus so far, the intrananomagnet excitations are well understood, however an understanding of the coupling between intra-and inter-mesospin degrees of freedom has not been developed for magnetic metamaterials.…”

“…artificial spin ices (ASI) [1][2][3][4][5], Ising chains and lattices [6,7], and reconfigurable magnonic crystals [8][9][10]. These magnetic metamaterials can be viewed as having thermal fluctuations, associated with switching of the magnetic states of the mesospins [11][12][13][14][15], in an activated process [12,13,16,17]. However, the magnetic fluctuations are not solely restricted to the switching of rigid mesospins, but can also occur in the interior textures of the mesospin, which necessitates a more nuanced view of their thermal excitations.…”