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

XLight plans to build massive “free electron lasers” powered by a particle accelerator to create a more powerful and precise light source for use in chip fabrication plants, or fabs.

From The Wall Street Journal

"By learning how to tame free electrons, we can imagine a future with faster computers, smarter machines, and new technologies we haven't even dreamed of yet."

From Science Daily

The team used a powerful laser, called a soft X-ray free electron laser, to emit ultrafast pulses of illumination at the speed of femtoseconds, or quadrillionths of a second.

From Science Daily

"What a fantastic scenario: Using free electrons to store CO2 and converting it to revenue-generating products is a concept I never would have imagined 10 years back, but this is just a start."

From Science Daily

In momentum space, free electrons are found in the local minima and maxima of the energy landscape, namely at points where the conduction and valence bands meet.

From Science Daily