molecular beam

American  

noun

Physics.

1. a stream of molecules freed from a substance, usually a salt, by evaporation and then passed through a narrow slit for focusing, for investigating the properties of nuclei, atoms, and molecules.

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molecular beam British  

noun

1. physics a parallel beam of molecules that are at low pressure and suffer no interatomic or intermolecular collisions

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Example Sentences

"Rather than ion implantation, molecular beam epitaxy was used to precisely incorporate gallium atoms into the germanium's crystal lattice," says Julian Steele, a physicist at the University of Queensland and a co-author of the study.

From Science Daily • Oct. 30, 2025

He developed a "molecular beam" consisting of a stream of molecules shot through a very fine slit into a vacuum tube.

From Time Magazine Archive

To simulate these peculiar conditions, California scientists use a peculiar apparatus: a "molecular beam" developed by Physicist Franklin C. Hurlbut.

From Time Magazine Archive

In the late 1950s Herschbach proposed to study what happens to individual molecules in the trillionth of a second of a chemical reaction by using the crossed molecular beam technique.

From Time Magazine Archive

Then Morey held it with a molecular beam, and I tried twisting it.

From The Black Star Passes by Campbell, John Wood