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Laser Switches Insulator to Conductor and Back in Femtoseconds

Ultrashort pulses of light could lead to petahertz-speed computing

3 min read
Laser Switches Insulator to Conductor and Back in Femtoseconds
Photo: Thorsten Naeser, LMU

11 December 2012—The best transistors today can switch on and off hundreds of billions of times a second. But laser pulses can be more than 10 000 times as quick. Now researchers in Germany have used such ultrashort laser pulses to induce current with the same kind of frequencies—creating an electric switch with laser speed. 

“Laser pulses are the shortest signal you can generate,” says Martin Schultze, a researcher at the Max Planck Institute of Quantum Optics, in Garching, Germany, who was involved in the work and is currently a visiting scientist at the University of California, Berkeley. “They are much faster than anything electronic.” 

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The Transistor at 75

The past, present, and future of the modern world’s most important invention

1 min read
A photo of a birthday cake with 75 written on it.
Lisa Sheehan

Seventy-five years is a long time. It’s so long that most of us don’t remember a time before the transistor, and long enough for many engineers to have devoted entire careers to its use and development. In honor of this most important of technological achievements, this issue’s package of articles explores the transistor’s historical journey and potential future.

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