Visualizing the electron's quantization with a ruler.


Journal

Scientific reports
ISSN: 2045-2322
Titre abrégé: Sci Rep
Pays: England
ID NLM: 101563288

Informations de publication

Date de publication:
25 05 2021
Historique:
received: 15 02 2021
accepted: 28 04 2021
entrez: 26 5 2021
pubmed: 27 5 2021
medline: 27 5 2021
Statut: epublish

Résumé

More than 100 years ago, Robert Millikan demonstrated the quantization of the electron using charged, falling droplets, but the statistical analysis on many falling droplets did not allow a direct visualization of the quantization of charge. Instead of letting the droplets fall, we have used optical levitation to create a single droplet version of Millikan's experiment where the effects of a single electron removal can be observed by the naked eye and measured with a ruler. As we added charges to the levitated droplet, we observed that its equilibrium position jumped vertically in quantized steps. The discrete nature of the droplet's jumps is a direct consequence of the single-electron changes in the charge on the droplet, and therefore clearly demonstrates the quantization of charge. The steps were optically magnified onto a wall and filmed. We anticipate that the video of these single electron additions can become a straightforward demonstration of the quantization of charge for a general audience.

Identifiants

pubmed: 34035337
doi: 10.1038/s41598-021-89714-2
pii: 10.1038/s41598-021-89714-2
pmc: PMC8149853
doi:

Types de publication

Journal Article Research Support, Non-U.S. Gov't

Langues

eng

Sous-ensembles de citation

IM

Pagination

10703

Références

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Auteurs

Javier Tello Marmolejo (JT)

Department of Physics, University of Gothenburg, 412 96, Gothenburg, Sweden. javier.marmolejo@physics.gu.se.

Mitzi Urquiza-González (M)

Department of Physics, University of Gothenburg, 412 96, Gothenburg, Sweden.
Facultad de Ciencias, Universidad Nacional Autónoma de México, Av. Universidad 3000, Circuito Exterior S/N Delegación Coyoacán, C.P. 04510 Ciudad Universitaria, Ciudad de México, México.

Oscar Isaksson (O)

Department of Physics, University of Gothenburg, 412 96, Gothenburg, Sweden.

Andreas Johansson (A)

Department of Physics, University of Gothenburg, 412 96, Gothenburg, Sweden.

Ricardo Méndez-Fragoso (R)

Facultad de Ciencias, Universidad Nacional Autónoma de México, Av. Universidad 3000, Circuito Exterior S/N Delegación Coyoacán, C.P. 04510 Ciudad Universitaria, Ciudad de México, México.

Dag Hanstorp (D)

Department of Physics, University of Gothenburg, 412 96, Gothenburg, Sweden.

Classifications MeSH