14 DAY TRIAL // Magnetic materials are rather abundant on Earth, especially under the form of magnetite mineral. Recently, researchers from the Advanced Photon Source of Argonne National Laboratory, in collaboration with colleagues from the Carnegie Institution's Geophysical Laboratory, have demonstrated that the magnetic properties of magnetite material are severely weakened while subjected to intense pressures. For example, magnetite under a pressure ranging between 120,000 to 160,000 times higher than that of the atmospheric pressure on Earth can experience a drop in magnetic field strength half of that measured under normal conditions.
The magnetic properties of materials are given by the orientation of spin of the electrons. A large number of unpaired electrons would ultimately determine the appearance of electrons with different spin orientation aligned with each other, to give magnetite strong magnetic properties. On the other hand, the researching team has shown that by applying extreme pressures on the material, the unpaired electrons will be forced into paired configurations, fact that decreases the strength of the magnetic field.
As I've said earlier, magnetic materials are common on Earth and can be found even in living organisms ranging from bacteria and birds all the way to humans. However, while birds make good use of their magnetite minerals in the sense that they have incredible navigation capabilities, humans have evolved to suppress such a valuable tool.
Understanding what generates magnetism has puzzled people ever since magnetic materials have been discovered and not much has changed even today. The behavior of magnetite is extremely hard to predict mostly due to the special electronic configuration, which determines the appearance of strong interactions inside it.
During the experiment conducted at the Advanced Photon Source Argonne Laboratory, the team analyzed a sample of magnetite material with the help of a X-ray Magnetic Circular Dichroism high-energy synchrotron. The sample is subjected to hundreds of thousands of times the pressure of the Earth's atmosphere with a diamond anvil and is probed for its magnetic state with high-brilliance circularly polarized X-rays.
Further theoretical calculations have proved that indeed the process responsible for the magnetic properties of materials is found in the electronic-configuration. The experiment has also been successful for the first time in proving that the electron mobility in a magnetic material is not dependent on the electronic spin pairing transition produced by the tremendous pressure.