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Skyrmion Dynamics in a Double-Disk Geometry under an Electric Current.

ABSTRACT: In this work, we present an analysis of skyrmion dynamics considering Dzyaloshinskii-Moriya interactions in an STNO device with a double-disk geometry. Three regimes were observed as a function of geometric parameters and the electric current density: (i) the skyrmion is annihilating at the system's border; (ii) the skyrmion moves in a non-circular trajectory alternating its position between the two disks, and (iii) the skyrmion only rotates inside a one-disk subsystem. For the annihilation state, we found that the transient time decays within a stretched exponential law as a function of the electric current. Our results show a 2D state diagram that can guide new experimental work in order to obtain these specific behaviors for new applications based on skyrmion dynamics.

SUBMITTER: Castillo-Sepulveda S

PROVIDER: S-EPMC9502721 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Skyrmion Dynamics in a Double-Disk Geometry under an Electric Current.

Castillo-Sepúlveda Sebastián S Vélez Javier A JA Corona Rosa M RM Carvalho-Santos Vagson L VL Laroze David D Altbir Dora D

Nanomaterials (Basel, Switzerland) 20220906 18

In this work, we present an analysis of skyrmion dynamics considering Dzyaloshinskii-Moriya interactions in an STNO device with a double-disk geometry. Three regimes were observed as a function of geometric parameters and the electric current density: (i) the skyrmion is annihilating at the system's border; (ii) the skyrmion moves in a non-circular trajectory alternating its position between the two disks, and (iii) the skyrmion only rotates inside a one-disk subsystem. For the annihilation stat ...[more]

PMID: 36144874

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