- #1
kmp
- 14
- 0
what is the difference between insulators and dielectrics?:
f95toli said:I disagree. it is correct to say that all dielectrics are insulators; but there are insulators that are not (usually) referred to as dielectrics.
A good example would be Mott insulators (I can also think of other examples, e.g. metallic superinsulators).
Note the "usually" above, I have heard of people referring to Mott insulators as dielectrics; but it is pretty uncommon and there is a case for reserving the word "dielectric" for materials which are insulating due to their band structure.
Gokul43201 said:I also disagree with the equivalence for somewhat pedantic reasons. While the terms are almost always used interchangeably in the field, they refer to different underlying electronic properties. A good insulator is therefore a material with low conductivity while a good dielectric is a material with high polarizability. Of course, a dielectric used in a capacitive role is almost always preferred when it also has lower conductivity.
An insulator is a material that does not conduct electricity, while a dielectric is a material that can become polarized in an electric field but does not allow the flow of current.
Insulators and dielectrics both have high resistance to electric fields, meaning they can restrict or prevent the flow of electricity. However, dielectrics can become polarized when placed in an electric field, which can enhance or diminish the overall strength of the field.
Insulators include materials such as rubber, glass, plastic, and wood. Dielectrics include materials such as air, water, and ceramics.
Insulators are commonly used to prevent the flow of electricity in electrical wiring, circuit boards, and electronic devices. Dielectrics are used in capacitors to store electric charge and in insulating coatings for wires and cables.
While insulators and dielectrics are primarily known for their high resistance to electricity, they can conduct electricity under certain conditions. For example, if the electric field is strong enough, air can become ionized and conduct electricity. Additionally, some dielectrics can conduct electricity at high frequencies or temperatures.