One way or another, computers will eventually incorporate aspects of quantum physics. They may be true ‘quantum computers’ or just use components based on quantum mechanics, but the trends are moving in the quantum direction. (I realize quantum direction is pretty much an oxymoron.) We’re almost at the end of the road for current silicon-based computation, or to use a more accurate metaphor – we’re at the end of the scale. With current technology we can’t cram many more circuits into the limited space of a CPU chip. Of course, the search is on for new technology, in this case new research into a resonant interband tunneling diode:
Researchers at Ohio State University have discovered a way to make quantum devices using technology common to the chip-making industry. Paul Berger, professor of electrical and computer engineering and professor of physics at Ohio State University, and his colleagues report their findings in an upcoming issue of IEEE Electron Device Letters.
The team fabricated a device called a tunneling diode using the most common chip-making technique, called chemical vapor deposition. “We wanted to do this using only the tools found in the typical chip-makers toolbox,” Berger said. “Here we have a technique that manufacturers could potentially use to fabricate quantum devices directly on a silicon chip, side-by-side with their regular circuits and switches.”
The quantum device in question is a resonant interband tunneling diode (RITD) — a device that enables large amounts of current to be regulated through a circuit, but at very low voltages. That means that such devices run on very little power. Tunneling diodes are so named because they exploit a quantum mechanical effect known as tunneling, which lets electrons pass through thin barriers unhindered. In theory, interband tunneling diodes could form very dense, very efficient micro-circuits in computer chips. A large amount of data could be stored in a small area on a chip with very little energy required.
[Source: Research News at Ohio State University]
Although the tunneling diode (RITD) has many potential uses (photography, medicine, military sensors), the Ohio State research has not quite cracked the manufacturing requirements (they need the device to reach a signal peak-to-valley ratio of 2; it’s now at 1.85). This comes under the heading of a ‘promising approach.’