The December 2022 issue of IEEE Spectrum is here!

Close bar

U.S. Energy Secretary Steven Chu's Latest Experiment

Chu's atom interferometer could lead to GPS without the satellites

3 min read

22 January 2009—The newly confirmed U.S. Secretary of Energy, Steven Chu, is settling into his new job in Washington, D.C., but he’s still making waves in his old job as a physicist. The former director of the Lawrence Berkeley National Laboratory, Chu presents in his latest paper one of the most promising developments yet in a fledgling quantum technology that may within a decade power satellite-free GPS, monitor earthquake zones, map out undiscovered mineral resources, and search for elusive gravitational waves.

The technology is based on the 85-year-old principle that particles of matter act like waves. Chu’s team, directed by physics assistant professor Holger Müller, of the University of California, Berkeley, nudged individual cesium atoms up a spout and watched the resulting patterns as the atoms fell onto a detector below.

Keep Reading ↓Show less

This article is for IEEE members only. Join IEEE to access our full archive.

Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, podcasts, and special reports. Learn more →

If you're already an IEEE member, please sign in to continue reading.

Membership includes:

  • Get unlimited access to IEEE Spectrum content
  • Follow your favorite topics to create a personalized feed of IEEE Spectrum content
  • Save Spectrum articles to read later
  • Network with other technology professionals
  • Establish a professional profile
  • Create a group to share and collaborate on projects
  • Discover IEEE events and activities
  • Join and participate in discussions
This photograph shows a car with the words “We Drive Solar” on the door, connected to a charging station. A windmill can be seen in the background.

The Dutch city of Utrecht is embracing vehicle-to-grid technology, an example of which is shown here—an EV connected to a bidirectional charger. The historic Rijn en Zon windmill provides a fitting background for this scene.

We Drive Solar

Hundreds of charging stations for electric vehicles dot Utrecht’s urban landscape in the Netherlands like little electric mushrooms. Unlike those you may have grown accustomed to seeing, many of these stations don’t just charge electric cars—they can also send power from vehicle batteries to the local utility grid for use by homes and businesses.

Debates over the feasibility and value of such vehicle-to-grid technology go back decades. Those arguments are not yet settled. But big automakers like Volkswagen, Nissan, and Hyundai have moved to produce the kinds of cars that can use such bidirectional chargers—alongside similar vehicle-to-home technology, whereby your car can power your house, say, during a blackout, as promoted by Ford with its new F-150 Lightning. Given the rapid uptake of electric vehicles, many people are thinking hard about how to make the best use of all that rolling battery power.

Keep Reading ↓Show less