free electron

American  

noun

Physics.

1. an electron that is not attached to an atom or molecule and is free to respond to outside forces.

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free electron British  

noun

1. any electron that is not attached to an ion, atom, or molecule and is free to move under the influence of an applied electric or magnetic field

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Etymology

Origin of free electron

First recorded in 1905–10

Example Sentences

Brighter soft X-ray free electron lasers are available which would enable even clearer images with less grainy "noise."

From Science Daily • May 24, 2024

In this way, the researchers simulate a complex state similar to the one produced in the solid state by a free electron.

From Science Daily • Oct. 26, 2023

In a free electron laser, a linear accelerator, or linac, shoots a beam of high-energy electrons into a string of complex magnets called undulators.

From Science Magazine • Sep. 18, 2023

Repeat the above example on Example 20.3, but for a wire made of silver and given there is one free electron per silver atom.

From Textbooks • Aug. 12, 2015

Charley danced and flicked around the cabin like a free electron with a careless disregard for traffic regulations and public safety.

From Master of the Moondog by Mullen, Stanley