Up until fairly recently Gordon Moore’s observation that the number of transistors in an integrated circuit doubles every two years has proven remarkably accurate. Transistors are continuing to shrink but halving their size today does not mean you can clock them at twice the speed. The limiting factor now is the energy lost in pushing electrons around the chip. Reducing processor core voltage helps to cut wasted energy, but lower switching thresholds and more crowded tracks increase the risk of signal crosstalk.

 

More recently microprocessor manufacturers have increased computing power by packing more processing cores into a single chip. Communication between the cores however adds significantly to losses.

 

A team of researchers working at the University of Colorado Boulder and MIT have produced a device which gives greater efficiency. They have developed a photonic optical modulator which converts a mass of electrical signals on the chip into optical wavelengths and squirts them down a single fiber.

 

Design of the optical modulators is such that they can be manufactured using the standard processes used to fabricate bulk CMOS and SOI CMOS chips.  This significantly reduces the need for investment in new process plant.