Polarization in Dielectrics

‘Polarization’, denoted by ‘P’ is defined as the difference between the induced electric field ‘D’ and imposed electric field ‘E’ within a dielectric medium due to immovable and free charge carriers respectively.

This phenomena occurs if an electric field distortion takes place between negatively charged electrons around positively charged atomic nuclei giving rise to slight difference of charges.

Mathematically, it is stated as-
P = (D-E)/4π

Polarization can also be expressed in terms of electric susceptibility Хe, such as,
P = є0 Хe E

Where, є0 = permittivity of free space, (= 8.85 x 10-12 Farad/metre).

Quantitatively, it is denoted by-

P = p/V
Where, p =amount of dipole moment

  V = volume of polarized material