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Updated: Sep 9, 2025

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Refrigeración magnética a muy baja temperatura Materiales inorgánicos: desde la síntesis diseñada hasta la

Qiao-Fei Xu¹, Ruo-Tong Wu¹, La-Sheng Long¹

¹Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

Accounts of chemical research

|August 29, 2025

Resumen

Los investigadores desarrollaron nuevos refrigerantes magnéticos para la refrigeración por desmagnetización adiabática (ADR) que logran altos cambios de entropía magnética (-ΔSm) y bajas temperaturas de ordenamiento (T0). Estos nuevos materiales avanzan significativamente el enfriamiento sin helio por debajo de 1 Kelvin para la computación cuántica y la astronomía.

Área de la Ciencia:

Ciencias de los materiales
Física de bajas temperaturas
Tecnologías Cuánticas

Sus antecedentes:

La refrigeración por desmagnetización adiabática (ADR) es la única tecnología libre de helio para el enfriamiento sub-Kelvin.
La creciente demanda en computación cuántica y astronomía requiere sistemas avanzados de ADR.
Los refrigerantes magnéticos existentes se enfrentan a una compensación entre el cambio de entropía magnética (-ΔSm) y la temperatura de ordenamiento (T0).

Objetivo del estudio:

Para diseñar racionalmente refrigerantes magnéticos de próxima generación para ADR.
Para superar el desafío de lograr un alto ΔSm y un bajo T0 simultáneamente.
Mejorar el rendimiento de la ADR para aplicaciones a temperaturas de millikelvin.

Principales métodos:

Parámetros magnéticos de ajuste: temperatura de ordenamiento (T0), intercambio e interacciones dipolares.
Incorporación de puentes de fluoruro en las estructuras antiferromagnéticas.
Utilizando la aproximación de campo medio y las simulaciones cuánticas de Monte Carlo (QMC).
Síntesis y ensayo de nuevos materiales como el Gd ((OH) F2, el LiGd0.1Yb0.9F4 y el KYb3F10.

Principales resultados:

La incorporación de fluoruro cambió el antiferromagnetismo al ferromagnetismo débil, reduciendo T0 y aumentando -ΔSm.
Gd(OH) F2 alcanzó valores récord de -ΔSm equilibrando las interacciones magnéticas débiles y la alta densidad magnética.
LiGd0.1Yb0.9F4 se enfría a 160 mK con el doble de la capacidad de refrigeración de los refrigerantes comerciales.
KYb3F10 alcanzó 27.2 mK, demostrando ser prometedor como refrigerante ADR de próxima generación.

Conclusiones:

Las estrategias de diseño racional mejoran con éxito -ΔSm y suprimen T0 en refrigerantes magnéticos.
Equilibrar las interacciones magnéticas y el desorden químico es clave para un alto rendimiento.
Los refrigerantes desarrollados proporcionan una vía sólida para el avance de la tecnología ADR en sistemas de baja temperatura fundamentales y aplicados.

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