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Ruido fractal y anómalo dinámico en un cristal magnético limpio
Jonathan N Hallén1,2, Santiago A Grigera3, D Alan Tennant4,5
1TCM Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK.
Science (New York, N.Y.)
|December 15, 2022
Resumen
Los investigadores descubrieron un fractal dinámico en el hielo de espín magnético, explicando el ruido magnético anómalo y los tiempos de relajación. Este hallazgo destaca comportamientos emergentes complejos en sistemas de muchos cuerpos topológicos simples.
Área de la Ciencia:
- Física de la materia condensada
- El magnetismo
- Sistemas complejos
Sus antecedentes:
- Los fractales se observan en toda la naturaleza a varias escalas.
- Comprender los fenómenos emergentes en los materiales magnéticos es crucial.
Objetivo del estudio:
- Identificar y caracterizar los fractales dinámicos emergentes en los sistemas magnéticos.
- Para explicar las observaciones experimentales anómalas en hielo de espín.
Principales métodos:
- Análisis teórico de las excitaciones del monopolio magnético en hielo de espín.
- Investigando las restricciones en la dinámica de excitación.
Principales resultados:
- Se identificó un fractal dinámico emergente en un cristal magnético libre de desorden.
- La dinámica fractal explica exponentes anómalos en el ruido magnético.
- La naturaleza fractal resuelve el rompecabezas de los tiempos de relajación divergentes.
Conclusiones:
- El hielo de espín exhibe dinámicas fractales emergentes de excitaciones de monopolio restringidas.
- Este descubrimiento proporciona una nueva perspectiva sobre la dinámica cooperativa en sistemas topológicos de muchos cuerpos.
- Otros fenómenos inesperados pueden existir en sistemas similares.
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