Antiferromagnetism is when electrons form chains of oppositely charged particles in a material, without any magnetic qualities. It is opposite to ferromagnetism, where particles align within domains. The Neel temperature is the highest level of magnetism in an antiferromagnetic material, and as temperature increases, magnetism decreases.
Antiferromagnetism is when electrons within a material come together, forming a chain of oppositely charged particles, even though the material as a whole does not appear to have any magnetic qualities. Antiferromagnetism is the opposite of ferromagnetism, where particles line up and occurs in materials such as manganese oxide. The phenomenon generally decreases as the temperature increases, the electrons disperse arbitrarily and no longer form chains. The temperature at which this occurs is referred to as the Neel temperature.
The name antiferromagnetism comes from the opposite term ferromagnetism. In ferromagnetism, the particles within a material align themselves within a domain so that within that specific domain, the material is magnetic. This can be difficult to find externally, because there are many different particle groups that are not aligned equally with each other. A ferromagnetic material is iron. The Latin word for iron, “ferrum,” is where the word “ferromagnetic” comes from. Ferromagnetic materials can be made magnetic with the use of an external magnetic field and are often used for electromagnets.
Antiferromagnetism means that the electrons within the material do not align with the same magnetic polarity. Even within the specific domains, the material exhibits no magnetic quality. Since the electrons don’t line up in the same polarity, they cancel each other out with the specific chain of electrons. This is different from ferromagnetism, because in ferromagnetic materials, the chains consist of electrons with corresponding polarity, but the different chains cancel each other out.
Louis Neel, a French physicist, discovered the temperature at which the highest possible level of magnetism can be produced in an antiferromagnetic material, now called the Neel temperature. As the temperature rises, some of the oppositely aligned particles can break free from their chains and arrange themselves according to an external field. Each material has a different Neel temperature; for example, that for manganese oxide is minus 240 degrees Fahrenheit (151 degrees Celsius), but others can be equal to or greater than room temperature. Above the Neel temperature, the electrons that break free from the chains produced by antiferromagnetism cannot form even the weak magnetic groups that they can form at lower temperatures. As the temperature increases, the level of disorder within the atomic structure of the material increases, thus decreasing its level of magnetism.
Protect your devices with Threat Protection by NordVPN
