Sciences & Technology

It’s easy to take digital technology for granted these days. To students who were practically born with an iPad in their hands, it’s hard to imagine a time when a world of history and knowledge wasn’t just a few swipes away.

Way back in the salad days of digital computing (the 1940s and '50s), computers were made of vacuum tubes -- big, hot, clunky devices that, when you got right down to it, were essentially glorified light bulbs. This is why early computers like the ENIAC weighed more than 27 tons and consumed more power than a small town. Later, obviously, vacuum tubes would be replaced by probably the greatest invention of all time -- the solid-state transistor -- which would allow for the creation of smaller, faster, cheaper, and more reliable computers. Fast forward to 2014, though, and the humble CMOS field-effect transistor (FET) is starting to show its age. We've pretty much hit the limit on shrinking silicon transistors any further, and they can't operate at speeds much faster than a few gigahertz. Which is why NASA's Ames Research Center is going back to the future with its new vacuum transistor -- a nanometer-scale vacuum tube that, in early testing, has reached speeds of up to 460GHz.

Unlike commercial airliners, modern military aircraft are subjected to ever-changing flying conditions—from high-thrust takeoffs to flying at altitude to combat maneuvers.

Everybody loves LEDs, as they're far more efficient and longer-lasting than traditional incandescent bulbs. They're also more economical to use in the long run, although they're costlier on a per-bulb basis. That price gap could soon be closing, however, as scientists have discovered a cheaper alternative to one of their most expensive ingredients.

White light-emitting LEDs use metals known as rare earth elements (REEs) for their phosphors – these are the materials that convert the light emitted from LED chips into longer wavelengths, allowing the bulbs to put out full-spectrum visible light.

The mining and processing of REEs is hazardous, however, leaving China as just about the only country currently supplying them in substantial quantities. This drives up their price, which could climb even higher as demand for LED-based technologies increases.

Led by Prof. Jing Li, a team of scientists from New Jersey's Rutgers University has now discovered that a family of materials made from relatively cheap and abundant copper iodide can be substituted for REEs.

You're looking a ribbon of graphene that's just one atom thick and fifteen atoms wide—and it could help shift data thousands of times faster than anything else currently can.
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