Curie–Weiss law

About: Curie–Weiss law is a research topic. Over the lifetime, 3501 publications have been published within this topic receiving 60002 citations.

On the Magnetic Properties of a CrBr 3 Single Crystal

Abstract: Magnetic properties of single crystals of CrBr 3 have been measured with a magnetic balance and also with a torque magnetometer. The ferromagnetic Curie point has been found to be 37°K from the temperature dependences of magnetization and of torque. Based on the data of the magnetic susceptibility above the Curie point, the paramagnetic Curie point θ p , Curie constant C M and the effective Bohr magneton number have been determined to be 47°K, 1.84 and 3.85 µ B respectively. From the saturation magnetization at 42°K, the moment of chromium ion is estimated to be 3 µ B , coinciding with the spin moment obtained from the susceptibility measurement above the Curie temperature. Direction of easy magnetization lies along the c -axis of the hexagonal lattice, and the second order and the fourth order anisotropy constants are estimated to be K 1 =-5.08×10 5 and K 2 =0.65×10 5 erg/cc respectively. In the present results, there is found a small deviation in the torque curves from simple sinusoidal form, L = K sin ...

Magnetic Isotherms in the Band Model of Ferromagnetism

Abstract: Calculations are given for the dependence on temperature and magnetic field strength H of the magnetization M of ferromagnetic metals treated on the basis of the itinerant electron model. The spin wave contribution to the low temperature magnetization is considered in the limits of strong and very weak ferromagnetism. For the first limit, problems related to the well-known divergence of the zero field differential susceptibility are briefly discussed. The main part of the paper is concerned with the single particle contributions to the magnetization and associated differential susceptibility for very weak ferromagnetism. A simple equation for the magnetic isotherms is obtained in this limit and shown to be valid over a wide temperature range including 0 °K and the Curie temperature. This equation implies that plots of M 2 against H / M at various temperatures in this range give a series of parallel straight lines. Recently measured isotherms for the material ZrZn 2 are analysed on the basis of the theory, and several characteristic properties of this material are obtained from the analysis.

Electronic and magnetic states in the giant magnetoresistive compounds.

Abstract: The paramagnetic insulator to ferromagnetic metal transition in lanthanum manganites and the associated magnetoresistive phenomena is treated by considering the localization due to random hopping induced by slowly fluctuating spin configurations and electron-electron interactions. The transition temperature and its variation with composition is derived. The primary effect of the magnetic field on transport is to alter the localization length, an effect which is enhanced as the magnetic susceptibility increases. Expressions for the conductivity, its variation with magnetic field, and its connection with magnetic susceptibility in the paramagnetic phase are given, and can be tested with further experiments. \textcopyright{} 1996 The American Physical Society.

Magnetic and transport characteristics on high Curie temperature ferromagnet of Mn-doped GaN

Abstract: Mn-doped GaN films on sapphire (0001) substrates were grown by molecular beam epitaxy system using ammonia as nitrogen source. The result of magnetization measurement gives Curie temperature as high as 940 K. The field and temperature dependencies of the magnetization show coexistence of ferromagnetic and paramagnetic phases. In addition, the temperature dependencies of electrical resistance and carrier concentration were measured to investigate the relation between the ferromagnetism and transport property. Below about 10 K, a similar anomalous increase of magnetization and resistance is observed.

Sr2CrOsO6 : End point of a spin-polarized metal-insulator transition by 5d band filling

Abstract: In the search for new spintronic materials with high spin polarization at room temperature, we have synthesized an osmium-based double perovskite with a Curie temperature of 725 K. Our combined exp ...