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Information dynamics and natural computing in two-skyrmion system

Hiroki Mori1,*, Soma Miki1,2,*,†, Kota Emoto1,*, Ryo Ishikawa3,4,5, Eiiti Tamura2,6, Hikaru Nomura4,5,7, Minori Goto4,5,8, and Yoshishige Suzuki4,5,9,10,11,*

  • *These authors contributed equally to this work.
  • †Contact author: soma.miki.d8@tohoku.ac.jp
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Phys. Rev. Research 8, 023173 – Published 18 May, 2026

DOI: https://doi.org/10.1103/4cb8-lhtb

Abstract

The probabilistic information flow and natural computational capability of a system with two magnetic skyrmions at room temperature have been experimentally evaluated. Probabilistic behavior has attracted attention for its potential to enable unconventional computing paradigms that achieve ultralow-energy computation. However, information propagation and computation in such systems are more complex than in conventional computers, making their visualization essential.

In this study, a two-skyrmion system confined within a square potential well at thermal equilibrium was analyzed using information thermodynamics. Transfer entropy and the time derivative of mutual information were employed to investigate the information propagation speed, the absence of a Maxwell’s demon in thermal equilibrium, and the system’s non-Markovian properties. Furthermore, it was demonstrated that the system exhibits a small but finite computational capability for the nonlinear XOR operation, potentially linked to hidden information in the non-Markovian system.

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Phys. Rev. Research 8, 023173– Published 18 May, 2026
  • Received 21 January 2026
  • Accepted 2 April 2026
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