Individual electron absorbed—Visible to the naked eye

Researchers at the University of Gothenburg observed the absorption of a single electron by a levitated droplet with magnification that made it visible with the naked eye and even measurable.

According to Javier Marmolejo, Ph.D., Department of physics at the University of Gothenburg the quantization of the electric charge is directly visible for the first time without advanced equipment or a complex statistical analysis.

They trapped a drop using a laser inside a strong electric field and added individual electrons by exposing it to alfa radiation. The drop performed quantized jumps each time it absorbed one or a few electrons. By magnifying the image of the droplet using a single lens, the researchers could see the effect of a single electron absorption and to measure the jumps with a ruler. The bright spot moved about one millimeter for every absorbed electron.

The drop had a diameter of 29 micrometers, approximately the thickness of a thin human hair. It contains around 3.7 x1015 negatively charged electrons. The feat is incredible when considering that the effect of adding single electron to a droplet that already has 3 700 000 000 000 000 is visible with the naked eye.

Original Release: Eureka Alert