热量如何在液体中传播
Kamran Behnia1, Kostya Trachenko2
1Laboratoire de Physique et d'Étude des Matériaux, (ESPCI - CNRS - Sorbonne Université), PSL Research University, Paris, France. Kamran.Behnia@espci.fr.
Nature communications
|February 27, 2024
概括
正常的液态-3在费米离子-费米离子散射时间低于普朗克时间时偏离标准行为. 集体刺激,或声音模式,可能携带热量,解释观察到的导热率.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 量子流体 量子流体
背景情况:
- 兰道的费米液体理论描述了通过准粒子散射的运输.
- 正常的液体3He只在非常低的温度下遵守这个理论.
研究的目的:
- 在液体3He.He.中调查标准费米液态行为的偏差.
- 确定负责在较高温度下传热的机制.
主要方法:
- 分析了液体3He的实验数据,从0.007K到3K.
- 提出了一个模型,将准粒子和集体激发对导热性的贡献纳入其中.
主要成果:
- 观察到偏差与低于普朗克时间的费米离子-费米离子散射时间相关.
- 证明热扩散率受到基本常数的限制.
- 确定了一种具有特定波向量和平均自由路径作为热载体的声音模式.
- 证明热导率是准粒子和声音贡献的总和.
结论:
- 集体激发 (声音模式) 在液体3He.He中充当显著的热载体.
- 拟议的两组件模型准确地解释了实验热导率数据.
- 结果表明,适用于量子和经典液体的最小热扩散度限制.
相关概念视频
01:25Heat Capacities of an Ideal Gas III
2.2K
The number of independent ways a gas molecule can move along straight line, rotate, and vibrate is called its degrees of freedom. Supposing d represents the number of degrees of freedom of an ideal gas, the molar heat capacity at constant volume of an ideal gas in terms of d is
2.2K
02:44Heating and Cooling Curves
22.8K
When a substance—isolated from its environment—is subjected to heat changes, corresponding changes in temperature and phase of the substance is observed; this is graphically represented by heating and cooling curves.
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
For instance, the addition of heat raises the temperature of a solid; the amount of heat absorbed depends on the heat capacity of the solid (q = mcsolidΔT). According to thermochemistry, the relation between the amount of heat absorbed or released by a substance, q, and its...
22.8K
01:12Heat Flow and Specific Heat
5.4K
Heat is a type of energy transfer that is caused by a temperature difference, and it can change the temperature of an object. Since heat is a form of energy, its SI unit is the joule (J). Another common unit of energy often used for heat is the calorie (cal), which is defined as the energy needed to change the temperature of 1 g of water by 1 °C, specifically between 14.5 °C and 15.5 °C, since the energy needed shows a slight temperature dependence. Another commonly used unit is...
5.4K
01:14Mechanisms of Heat Transfer I
4.2K
Just as interesting as the effects of heat transfer on a system are the methods by which the heat transfer occur. Whenever there is a temperature difference, heat transfer occurs. It may occur rapidly, such as through a cooking pan, or slowly, such as through the walls of a picnic ice box. So many processes involve heat transfer that it is hard to imagine a situation where no heat transfer occurs. Yet, every heat transfer takes place by only three methods: conduction, convection, and radiation.
4.2K
01:20Conduction, Convection and Radiation: Problem Solving
1.2K
There are three methods by which heat transfer can take place: conduction, convection, and radiation. Each method has unique and interesting characteristics, but all three have two things in common: they transfer heat solely because of a temperature difference; and the greater the temperature difference, the faster the heat transfer.
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
1.2K
02:39Phase Transitions: Melting and Freezing
12.4K
Heating a crystalline solid increases the average energy of its atoms, molecules, or ions, and the solid gets hotter. At some point, the added energy becomes large enough to partially overcome the forces holding the molecules or ions of the solid in their fixed positions, and the solid begins the process of transitioning to the liquid state or melting. At this point, the temperature of the solid stops rising, despite the continual input of heat, and it remains constant until all of the solid is...
12.4K