Select your localized edition:

Close ×

More Ways to Connect

Discover one of our 28 local entrepreneurial communities »

Be the first to know as we launch in new countries and markets around the globe.

Interested in bringing MIT Technology Review to your local market?

MIT Technology ReviewMIT Technology Review - logo

 

Unsupported browser: Your browser does not meet modern web standards. See how it scores »

It makes intuitive sense that if superconductors can carry currents with zero resistance, then superconducting light emitting diodes might do their stuff with equally amazing efficiency.

But superconducting LEDs are not only bright, they are brighter than anyone can explain, even after taking superconductivity into account. Now a team of Japanese theorists seems to have figured out the puzzle.

The mystery began last year when Japanese researchers built a device to study the way in which Cooper pairs in superconducting niobium would emit light when combining with holes generated in a PN junction. To their surprise, the researchers found that their superconducting LED was not only bright but outshone their expectations by an order of magnitude. What on Earth was going on?

Now Yasuhiro Asano at Hokkaido University in Japan and a few buddies say that the effect can be explained by two peculiar second order effects that occur together only in superconductors. The so-called “giant oscillator strength” and a resonant effect both allow much higher numbers of Cooper pairs than expected to combine with holes and produce photons. This explains the result, say Asano and co.

This is exciting not just because superconducting LEDs will be bright but because Cooper pairs can also produce entangled pairs of photons. That raises the prospect of intense sources of entangled pairs, the likes of which physicists have not yet seen. And that could be hugely useful for everything from quantum communication to quantum teleportation.

Ref: arxiv.org/abs/0905.1182: Luminescence of a Cooper Pair

0 comments about this story. Start the discussion »

Tagged: Energy

Reprints and Permissions | Send feedback to the editor

From the Archives

Close

Introducing MIT Technology Review Insider.

Already a Magazine subscriber?

You're automatically an Insider. It's easy to activate or upgrade your account.

Activate Your Account

Become an Insider

It's the new way to subscribe. Get even more of the tech news, research, and discoveries you crave.

Sign Up

Learn More

Find out why MIT Technology Review Insider is for you and explore your options.

Show Me
×

A Place of Inspiration

Understand the technologies that are changing business and driving the new global economy.

September 23-25, 2014
Register »