Dielectric

Not to be confused with dielectric constant or dialectic.
A polarised dielectric material
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In electromagnetism, a dielectric (or dielectric medium) is an electrical insulator that can be polarised by an applied electric field. When a dielectric material is placed in an electric field, electric charges do not flow through the material as they do in an electrical conductor, because they have no loosely bound, or free, electrons that may drift through the material, but instead they shift, only slightly, from their average equilibrium positions, causing dielectric polarisation. Because of dielectric polarisation, positive charges are displaced in the direction of the field and negative charges shift in the direction opposite to the field. This creates an internal electric field that reduces the overall field within the dielectric itself. If a dielectric is composed of weakly bonded molecules, those molecules not only become polarised, but also reorient so that their symmetry axes align to the field.[1]

The study of dielectric properties concerns storage and dissipation of electric and magnetic energy in materials.[2][3][4] Dielectrics are important for explaining various phenomena in electronics, optics, solid-state physics and cell biophysics.[5][6]

  1. ^ "Dielectric". Encyclopædia Britannica. Chicago, Illinois: Encyclopædia Britannica, Inc. Archived from the original on 27 April 2021. Retrieved 20 November 2021. Dielectric, insulating material or a very poor conductor of electric current. When dielectrics are placed in an electric field, practically no current flows in them.
  2. ^ Arthur R. von Hippel, in his seminal work, Dielectric Materials and Applications, stated: "Dielectrics... are not a narrow class of so-called insulators, but the broad expanse of nonmetals considered from the standpoint of their interaction with electric, magnetic or electromagnetic fields. Thus we are concerned with gases as well as with liquids and solids and with the storage of electric and magnetic energy as well as its dissipation." (p. 1) (Technology Press of MIT and John Wiley, NY, 1954).
  3. ^ Thoms, E.; Sippel, P.; et., al. (2017). "Dielectric study on mixtures of ionic liquids". Sci. Rep. 7 (1): 7463. arXiv:1703.05625. Bibcode:2017NatSR...7.7463T. doi:10.1038/s41598-017-07982-3. PMC 5547043. PMID 28785071.
  4. ^ Belkin, A.; Bezryadin, A.; Hendren, L.; Hubler, A. (2017). "Recovery of Alumina Nanocapacitors after High and Low Voltage Breakdown". Sci. Rep. 7 (1): 932. Bibcode:2017NatSR...7..932B. doi:10.1038/s41598-017-01007-9. PMC 5430567. PMID 28428625.
  5. ^ Hossain, Shadeeb (2020-12-27). "Malignant cell characterisation via mathematical analysis of bio impedance and optical properties". Electromagnetic Biology and Medicine. 40 (1): 65–83. doi:10.1080/15368378.2020.1850471. ISSN 1536-8378. PMID 33356700. S2CID 229694503.
  6. ^ Hossain, Shadeeb (2020-04-02). "Biodielectric phenomenon for actively differentiating malignant and normal cells: An overview". Electromagnetic Biology and Medicine. 39 (2): 89–96. doi:10.1080/15368378.2020.1737804. ISSN 1536-8378. PMID 32138569. S2CID 212565141.