I don't know when optical quantum computers are going to arrive, but I sure hope they look like this crazy Toshiba visualization of an Entangled Light Emitting Diode. This new LED type could finally make practical quantum computers possible.
According to Mark Stevenson—from Toshiba Research Europe—experts, the current breed of laser-based optical quantum computing experiments can't result in a practical device. His team has been the first to create something compact enough to form the basis for this kind of computer without the complexity, price, and size of laser-based options:
We have generated entangled light using an electric current for the first time. All previous sources of entangled light used lasers to drive them. As ELEDs are electrically controlled and many devices can be integrated on a single chip, they could meet these demands in a simple, compact and affordable way. Although one could imagine a quantum computer running on laser-driven sources, the complexity and demands on space and maintenance for a large number of sources means this would be impractical.
Toshiba hopes this new invention will lead to commercial versions that could be applied for quantum processors, imaging, and communications. [Optics]