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Kyoung-Min Kim

Reconfigurable all-in-one chaos computing using moiré skyrmions in twisted van der Waals magnet

2025 KMS Winter Conference, November 27, 2025

In collaboration with Dr. Gyuyoung Park and Dr. Okjae Lee at KIST

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Chaos computing

  • A unconventional computing that leverages extreme sensitivity to initial conditions in chatotic systems

CHAOS 20, 037107 (2010)

 

 

 

 

  • Inherent nonlinearity allows reconfigurable multi-purpose logic gates
  • Random number generation, cryptographic security
  • Realized in an electric circuit, “ChaoGate”

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Reconfigurable chaos logic gate using a skyrmion

  • Skyrmion dynamics subject to VCMA

 

 

Gyuyoung Park and Sang-Koog Kim, PhysRevB.109.174420 (2024)

  • Logic gates from different modulation patterns

“Chaos”(nonlinearity)-enhanced diverse modulation patterns

 

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Magnetic domains in twisted bilayer CrI3

  • Twisted bilayer CrI3

Top

Bottom

 

  • Patterned interlayer exchange
  • Stabilization of magnetic domains and skyrmions

PhysRevResearch.3.013027 (2021)

Science, 374, 1140 (2021)

  • Nanoscale magnetic domains
  • Moiré superlattice

Chaotic magnetization dynamics

Magnetic chaos logic gates

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Micromagnetics in twisted bilayer CrI3

 

 

  • 300 nm x 300 nm, periodic boundary conditions

 

 

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Two local energy minimized configurations

 

Top-bottom layer symmetry

 

Two stable configurations

  • Top layer
  • Bottom layer
  • Top layer
  • Bottom layer
  • Configuration 1
  • Configuration 2

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Multiple domain structures in global energy minimized configuration

 

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“Chaotic” magnetization dynamics

Relaxation

Time

“Readout”

Relaxation

Relaxation

Relaxation

Initialization

“Readout”

Initialization

“Readout”

Initialization

“Readout”

Initialization

 

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0.

Confirmation of chaotic dynamics (1)

 

Maximally random!

0.5

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Confirmation of chaotic dynamics (2)

0.

 

 

 

 

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Summary & outlook

Chaos computing: reconfigurable logic gates through sensitivity to initial conditions

 

 

 

How to implement chaotic computing scheme (VCMA-based magnetization dynamics)

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Thank you