The new composite prevents malfunctions of electronic devices

Scientists from South Ural State University, in collaboration with colleagues from Belarus, India and China, have created a composite material for nanoelectronics. The material can be used as a dielectric (insulating substance) ...

Study finds electrical fields can throw a curveball

MIT researchers have discovered a phenomenon that could be harnessed to control the movement of tiny particles floating in suspension. This approach, which requires simply applying an external electric field, may ultimately ...

Mechanically controllable nonlinear dielectrics

Strain-sensitive barium strontium titanate (Bax-Sr1-x-TiO3) perovskite systems are widely used for their superior nonlinear dielectric behaviors. In a new report on Science Advances, D.L. Ko and a research team in materials ...

Molecular probe maps misfolded proteome state in live cells

The folding state of the proteins in live cells often reflect the cell's general health. Australian scientists have developed a molecular probe that senses the state of the proteome—the entire set of the proteins—by measuring ...

Jumping the gap may make electronics faster

A quasi-particle that travels along the interface of a metal and dielectric material may be the solution to problems caused by shrinking electronic components, according to an international team of engineers.

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A dielectric is an electrical insulator that can be polarized by an applied electric field. When a dielectric is placed in an electric field, electric charges do not flow through the material, as in a conductor, but only slightly shift from their average equilibrium positions causing dielectric polarization. Because of dielectric polarization, positive charges are displaced toward the field and negative charges shift in the opposite direction. This creates an internal electric field which reduces the overall field within the dielectric itself. If a dielectric is composed of weakly bonded molecules, those molecules not only become polarized, but also reorient so that their symmetry axis aligns to the field.

Although the term "insulator" implies low electrical conduction, "dielectric" is typically used to describe materials with a high polarizability. The latter is expressed by a number called the dielectric constant. A common, yet notable example of a dielectric is the electrically insulating material between the metallic plates of a capacitor. The polarization of the dielectric by the applied electric field increases the capacitor's surface charge.

The study of dielectric properties is concerned with the storage and dissipation of electric and magnetic energy in materials. It is important to explain various phenomena in electronics, optics, and solid-state physics.

The term "dielectric" was coined by William Whewell (from "dia-electric") in response to a request from Michael Faraday.

This text uses material from Wikipedia, licensed under CC BY-SA