Researchers edge closer to optical computer

London, July 04: An optical transistor, successfully crafted from a single molecule, brings researchers a step closer to an optical computer, which would be much faster and more powerful than existing counterparts.

Existing central processing units (CPUs) limit the performance of computers, for example, because they produce an enormous amount of heat.

The millions of transistors that switch and amplify the electronic signals in the CPUs are responsible for this. One square cm of CPU can emit up to 125 watts of heat, which is more than 10 times as much as a square cm of an electric hotplate.

This is why scientists have been trying for some time to find ways to produce integrated circuits that operate on the basis of photons instead of electrons.

The reason is that photons not only generate much less heat than electrons, but they also enable considerably higher data transfer rates.

Although a large part of the existing telecom engineering is based on optical signal transmission, the necessary encoding of the information is generated using electronically controlled switches. A compact optical transistor is still a long way off.

Vahid Sandoghdar, professor at the Lab of Physical Chemistry of ETH Zurich, explains that “comparing the current state of this technology with that of electronics, we are somewhat closer to the vacuum tube amplifiers that were around in the fifties than we are to today’s integrated circuits”.

His research group has now achieved a decisive breakthrough by successfully creating an optical transistor with a single molecule, said a release of ETH Zurich.

–Agencies