Molecular memory

What happens when computers need so much memory that they start to test the laws of physics? Charlie Tizzard investigates.

A new way to store data in individual molecules might put some life back into an old law of computing. Back in 1965, the founder of Intel, Gordon Moore, noticed that computer chips doubled their performance about every 18 months. Not only was he right in 1965, he kept on being right. Ten, twenty, even thirty years later, chip power still doubled every 18 months. This observation was so strong that it began to seem like a law of nature. It was named “Moore’s law” after Gordon Moore himself.

But some experts believe that Moore’s law is beginning to waver. As electronics continue to get smaller and smaller they are pushing the law to the limit. Electronics are now so small that even the laws of physics are even getting in the way. An esteemed physicist, Michio Kaku, said that "we already see a slowing down of Moore's law. Computing power simply cannot maintain its rapid exponential rise using standard silicon technology.”

What to do?

Unless we move away from silicon-based storage in computing, we will run into some serious issues in the near future. Fortunately, scientists and engineers are experimenting with alternative ways of storing data. One way is to use molecules whose atoms can be shifted around within them. Storing data is all about making physical changes to something. That means you can put information in molecules by representing it as different atomic states. Best of all, those states can be changed and read by the same technology we have today: changes to the amount of electricity the molecules conduct.

Our only problem is that this idea works great inside a lab setting, but it can be difficult in the real world. First of all, molecular storage needs to be mass produced, but so far it’s specialised equipment built only in labs. Not only that, but up until now the molecules had to be kept at almost absolute zero (that’s -273°C) in order to work. But now an international team of researchers at MIT led by Jagadeesh Moodera have pioneered a new technique that allows the molecules to be kept at roughly the freezing point of water. In physics that’s practically room temperature.

Even more importantly, the molecules, which previously had to be sandwiched between two electrical conductors, only require one conductor in the MIT setup. That will make mass manufacturing a lot simpler and cheaper for companies. “This is only the tip of tip of the iceberg” says Moodera, so don’t be surprised if you are using chemicals for storing your photos in the future!