The electromagnetic nature of nanoparticles (based on nano-micro-electronics PHD

Researcher  and author: PhD student    Afshin Rashid


Note: The electromagnetic nature of nanoparticles in magnetic materials, molecules and their constituent atoms  have electromagnetic properties. Simply put, elements such as iron, cobalt, nickel, and their alloys are absorbed by the magnet  It is called magnetic material.

The classification of electromagnetic materials is based on the magnetic acceptability (material's magnetization capability). Based on this, the materials are classified into three groups: ferromagnetic, paramagnetic and diamagnetic. The resultant dipole moment in the material diamagnetic electromagnetic zero and in the presence of a magnetic field, torque  bipolar instilled in them; but to the dipole  induced against the external magnetic field that causes matter of (diamagnetic) of the magnetic field disposal Be. By removing the external magnetic field, the magnetic property of these materials does not remain. The magnetic acceptability of these materials is negative and very low (about 6-10 - up to 3-10). All gases (except oxygen) are water, silver, gold, copper, diamonds, graphite, bismuth, and many organic compounds ( diamagnetic). Magnetic poles In paramagnetic matter, they do not have a clear and regular orientation; therefore, these materials do not have magnetic properties. If they are placed inside a magnetic field, they become regular along the lines of  the magnetic field. By removing the magnetic field  , the magnetic dipoles return quickly to their previous state in the absence of the field. Thus, paramagnetic materials have strong magnetic properties in nanoroelectric fields. The positive value of electromagnetic susceptibility (about 6-10 to 1-10. (Manganese, platinum, aluminum, alkali metals and  alkaline earth oxide nano-paramagnetic oxygen and nitrogen  , such as paramagnetic material is  there. Ferromagnetic materials  with a difference That a set of magnetic dipoles are  in the same direction as the sets themselves. They are placed in different directions and directions, so  that they neutralize each other's field effect. This set  of magnetic dipoles, which are in the same direction, is called the nanoelectromagnetic field. The nanoelectromagnetic property of the particles of these  materials depends on the rapid change of direction of these fields and their position in the  direction of the field



The magnetic property depends to a large extent on the particle size  . Each magnetic substance in the mass state  is composed of magnetic fields. Each sphere has  thousands of atoms in which the electrons rotate in the same direction  and the magnetic moments are directed in parallel  But the direction of rotation of the electron in each domain is different from other domains  Whenever a large magnetic field directs all magnetic fields, a change in the nanoelectrical phase of the magnet occurs and the magnetization reaches saturation  Any particle that contains only one sphere  can be considered a nanoparticle. Magnetic nanoparticles have  a small number of domains and are easier to magnetize  


Conclusion:

In ferromagnetic materials, when the particle size is  smaller than a single magnetic field, the phenomenon of  paramagnetic cloud (non-connection of  nanoparticles in nanoscale under normal conditions and their high sensitivity to the magnetic field  ) occurs. Because nanoparticles do not require  much force to be magnetized, they are not far from  normal and, after being magnetized, do not have much of a tendency  to lose their magnetic properties and return  to their original state.

Author: Engineer Afshin Rashid  

PhD student in Nano-Microelectronics at Islamic Azad University, Science and Research Branch, Tehran