Diamagnets magnetic permeabilities

PERMEABILITY MAGNETIC SUSCEPTIBILITY MAGNETIC SUSCEPTIBILITY PARAMAGNETIC HEMOGLOBIN DIAMAGNETIC Magnetization,... 

The tendency of the magnetic lines of force to pass through a medium relative to their tendency to pass through a vacuum is the magnetic permeability, p. This is one of the parameters that distinguishes a diamagnetic material from a paramagnetic substance. Permeability is defined as. 

The paper also proves that the fluid region where turbulent motion occurs expels the external magnetic field like a diamagnetic body with low magnetic permeability /i. In the two-dimensional case considered in this paper, fi turns out to be of order (Rem)-1. However, the assertion regarding the diamagnetic properties of the turbulent motion is valid for the three-dimensional case as well. Here we find p (Rem)-1 (see review ). The next article in this collection is devoted to further development of the results obtained in this paper. 

The magnetic permeability, [x, is the ratio of the flux [ix, number of lines of force per unit cross section) in the substance to that in a vacuum. The ratio is greater than unity for a paramagnetic substance and less, but not much less, than unity for a diamagnetic one (Fig. 32). 

Thus from the above equation it is clear that the magnetic permeability of diamagnetic materials is slightly below unity, while that of the paramagnetic materials is greater than unity. 

Table 7.5. Magnetic susceptibilities and magnetic permeabilities of diamagnets ...

Diamagnets Magnetic susceptibility (10 %) Relative magnetic permeability (p,)... 

This simple equation applies to non-absorbing gases with the magnetic permeability, equal to unity for all diamagnetic gases except oxygen which is paramagnetic (see Chapter 7),... 

There are two aspects to perfect diamagnetism in superconductors. The first is magnetic field exclnsion if a material in the normal state is zero field cooled (ZFC), that is, cooled below Tc to the superconducting state withont any magnetic field present, and then it is placed in an external magnetic field, the field will be excluded from the superconductor. The second aspect is magnetic field expulsion. If the same material in its normal state is placed in a magnetic field, the field will penetrate and have almost the same value inside and outside because the permeability fx is so close to the free space value fXo. If this material is then field cooled (FC), that is, cooled below E in the presence of this applied field, the field will be expelled from the material this is the Meissner effect that was mentioned earlier. 

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