# Michigan Physicists Build an 'Electron Lighthouse' That Steers Current With Light Alone

*2026-07-29 10:01 UTC · Science · 1 min read*

> University of Michigan physicists used two-color laser light to steer a beam of electrons through a semiconductor with no electric field, an effect they call an 'electron lighthouse.'

Researchers at the University of Michigan, led by doctoral student Yiming Gong and senior author Steven Cundiff, have built a semiconductor device that directs the flow of electrons using only laser light — no applied electric field needed. The team calls the effect an "electron lighthouse."

Two different colors of laser light strike the semiconductor simultaneously, sending it through multiple absorption pathways at once. Quantum interference between those pathways reinforces electron motion in one direction while canceling it out in others, concentrating the flow into a narrow, controllable beam that can be swept like a lighthouse beam by changing the laser colors. "The light no longer merely switches the current on; it also aims it," Cundiff said.

The work, published in Physical Review Letters with collaborators from the University of Toronto and Sun Yat-Sen University and support from the U.S. National Science Foundation, could feed into faster optical sensors, communications hardware, imaging systems and information storage by merging optics and electronics more tightly.

## Sources

- [sciencedaily.com](https://www.sciencedaily.com/releases/2026/07/260727214601.htm)
- [sciencealert.com](https://www.sciencealert.com/physicists-created-an-electron-lighthouse-that-steers-current-with-light)

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TechTools News · https://techtools.cz/tools/news/article/2093-michigan-physicists-build-an-electron-lighthouse-that-steers-current-with-light
Česká verze: https://techtools.cz/tools/news/clanek/2166-fyzici-z-michiganu-sestrojili-elektronovy-majak-ktery-ridi-proud-pouze-pomoci