Skip to main content

My Gold Atom Weighs More Than Yours

Researchers at UC Berkley and Berkley Lab have developed a scale sensitive enough to measure, at room temperature, the mass of a single atom of gold, in a little over a second of time.

Although scientists can already measure the mass of a single atom using mass spectrometry, this new method is based on nanoelectromechanical (NEMS) technology, making it more sensitive and compact. So small is the sensor, researchers say it could eventually be put on a chip.

The mass sensor is made of a single carbon nanotube enclosed in two walls to increase rigidity and ensure uniform electrical properties, one end of the nanotube waves freely while the other is connected to an electrode near a counter electrode.

Appyling a DC voltage source allows researchers to create a negative electrical charge on the free end of the carbon nanotube, making it vibrate with a specific resonance frequency. Subsequently, the device works by measuring the change in resonance frequency of the carbon nanotube under the weight of the molecule or atom.

Comments

Popular Posts

How 4,000 Physicists Gave a Vegas Casino its Worst Week Ever

What happens when several thousand distinguished physicists, researchers, and students descend on the nation’s gambling capital for a conference? The answer is "a bad week for the casino"—but you'd never guess why.

Ask a Physicist: Phone Flash Sharpie Shock!

Lexie and Xavier, from Orlando, FL want to know:
"What's going on in this video? Our science teacher claims that the pain comes from a small electrical shock, but we believe that this is due to the absorption of light. Please help us resolve this dispute!"

The Science of Ice Cream: Part One

Even though it's been a warm couple of months already, it's officially summer. A delicious, science-filled way to beat the heat? Making homemade ice cream.

(We've since updated this article to include the science behind vegan ice cream. To learn more about ice cream science, check out The Science of Ice Cream, Redux)

Over at Physics@Home there's an easy recipe for homemade ice cream. But what kind of milk should you use to make ice cream? And do you really need to chill the ice cream base before making it? Why do ice cream recipes always call for salt on ice?