Influence of the strong magnetocrystalline anisotropy on the magnetocaloric properties of MnP single crystal

Manganese monophosphate MnP single crystal deserves attention due to its rich magnetic phase diagram, which is quite different depending on the direction of the applied magnetic field. Generally speaking, it has a Curie temperature around 291 K and several other magnetic arrangements at low temperatures (cone-, screw-, fan-, and ferromagnetic-type structures). This richness is due to the strong magnetocrystalline anisotropy. In this sense, the present paper makes a thorough description of the influence of this anisotropy on the magnetocaloric properties of this material. From a fundamental view we could point out, among those several magnetic arrangements, the most stable one. On the other hand, from an applied view, we could show that the magnetic entropy change around room temperature ranges from -4.7 to -3.2 J/kg K, when the magnetic field (5T) is applied along the easy and hard magnetization directions, respectively. In addition, we have shown that it is also possible to take advantage of the magnetic anisotropy for magnetocaloric applications, i.e., we have found a quite flat magnetic entropy change (with a huge relative cooling power), at a fixed value of magnetic field, only rotating the crystal by 90 degrees.771

Self-Organization of Plutonomy in a Fair Competitive Society

We investigate the origin of the emergence of the plutonomy, an extreme form of hierarchy, where the top 1% of households account for more wealth than the bottom 99%. For a model fair society where individuals participate in a competition with equal right, we show that the plutonomy can be self-organized when individuals divided into several groups compete with those in the same group for a certain period (season) and they are regrouped at the end of every season. In the fair society, the wealth flows steadily from lower groups to the highest group, which is the origin of the plutonomy. Using mean-field analysis, we show that the fraction of winners decreases in proportion to the inverse of the number of groups

Influence Of The Strong Magnetocrystalline Anisotropy On The Magnetocaloric Properties Of Mnp Single Crystal

Manganese monophosphate MnP single crystal deserves attention due to its rich magnetic phase diagram, which is quite different depending on the direction of the applied magnetic field. Generally speaking, it has a Curie temperature around 291 K and several other magnetic arrangements at low temperatures (cone-, screw-, fan-, and ferromagnetic-type structures). This richness is due to the strong magnetocrystalline anisotropy. In this sense, the present paper makes a thorough description of the influence of this anisotropy on the magnetocaloric properties of this material. From a fundamental view we could point out, among those several magnetic arrangements, the most stable one. On the other hand, from an applied view, we could show that the magnetic entropy change around room temperature ranges from -4.7 to -3.2 J kg K, when the magnetic field (5 T) is applied along the easy and hard magnetization directions, respectively. 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