蜂螺旋旋液候选中的巨大磁热效应
Yuqian Zhao1, Xun Chen1, Zongtang Wan1
1Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|August 26, 2025
概括
研究人员探索了螺旋旋液体 (SSL) 材料在磁冷却方面的潜力. 他们发现GdZnPO具有巨大的磁热效应,使其成为低温磁制冷的有希望的候选者.
科学领域:
- 凝聚物质物理学
- 材料科学
- 热力学
背景情况:
- 传统的磁性状态缺乏退化,与螺旋旋流体 (SSL) 不同,它们在退化的螺旋配置中波动.
- 从铁磁到SSL状态的 induced交叉可以增加,表明磁冷却的潜力,尽管尚未报告.
- 单晶GdZnPO是旋转-7/2蜂晶格SSL的候选物.
研究的目的:
- 研究GdZnPO的磁热效应和冷却性能.
- 确定GdZnPO在低温磁性制冷中的潜力.
- 在GdZnPO中验证SSL状态的稳定性.
主要方法:
- 在磁场下研究了GdZnPO的磁热效应 (H < Hc ≈ 12 T) 垂直于蜂平面和2 K以下.
- 分析了GdZnPO的磁性冷却性能.
- 使用挫败的蜂旋转模型来解释观察到的磁热效应.
主要成果:
- GdZnPO在Hc附近表现出巨大的低温磁热效应,超过其他材料.
- 观察到的磁热效应与理论模型一致,表明SSL在低于Hc的温度下保持稳定.
- GdZnPO具有高达4.5K的强大磁性冷却性能,冷却能力低至约36mK.
结论:
- 由于其巨大的磁热效应,GdZnPO是磁性制冷的一个有前途的材料.
- 在GdZnPO中,螺旋旋液态的稳定性得到证实.
- 在非常低的温度下,GdZnPO具有高效的磁冷功能.
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