Insulators turn up the heat on quantum bits

Physicists have long suspected that dielectric materials may significantly disrupt ion-trap quantum computers. Now, researchers led by Tracy Northup have developed a new method to quantify this source of error for the first ...

Smart dielectric elastomers for self-healing soft robots

Robots that resemble organs are known as soft robots, and in order for them to function they must be made of a flexible material, however a material that can also heal itself would be a bonus if wear and tear was to occur. ...

Finding high-Q resonant modes in a dielectric nanocavity

Optical resonators provide the foundation of modern photonics and optics. Thanks to its extreme energy confinement, the high-Q-factor optical resonator optimizes light-matter interaction and photonic device performance by ...

Alcohols exhibit quantum effects

Skoltech scientists and their colleagues from the Russian Quantum Center revealed a significant role of nuclear quantum effects in the polarization of alcohol in an external electric field. Their research findings are published ...

Researchers invent broad-band tunable terahertz absorber

Recently, a research team led by Prof. SHENG Zhigao from the High Magnetic Field Laboratory of the Hefei Institutes of Physical Science (HFIPS), along with collaborators in HFIPS and ShanghaiTech University, invented a broad-band ...

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 ...

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Dielectric

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.

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