Life inside a laser

For the first time ever, researchers have seen the electrical forces that ebb and flow at the centre of a laser in real time. U of T researchers led by Ted Sargent published a 3-D map of electron activity inside a working laser in the June 9 issue of Applied Physics Letters.

The researchers used a diamond coated silicon tip only ten nanometers wide to make the voltage measurements.

“How that voltage distributes itself across the laser is of great interest,” said Scott Kuntze, a Master’s student working under Sargent. “If we can understand that we [can] understand how the laser works.”

Understanding where the electrons are going is an important first step towards improved manufacturing and efficient laser designs. Results already show leakage in some lasers.

“In the next iteration, designers will now know that they’re losing this current,” says Kuntze.

Looking ahead, Sargent’s group will continue to perfect and broaden the technique to help test theoretical models of lasers that have for years gone without experimental verification.

-Ian ha

Oldest planet found

Astronomers using NASA’s Hubble Space Telescope have identified the oldest known planet, a gas giant located 5,600 light years away. The planet is 2.5 times the mass of Jupiter and at 12.7 billion years, is only a billion years younger than the universe itself. The planet had been detected more than a decade ago, but its status as a planet was debated throughout the 1990s.

Recent work using precise observations from Hubble allowed the researchers to calculate its mass and determine that it is indeed a planet. It orbits around two stars in a “globular” star cluster. Globular clusters are giant balls of stars which were formed early in the universe’s evolution. It was thought that globular clusters could not contain planets, since they contain few of the necessary heavy elements. The discovery shows that planets were forming far earlier than expected, suggesting that there may be more planets in the universe than previously thought.

-Qing Hua Wang
Source: NASA