Light transistors for computers

2001/04/25 Galarraga Aiestaran, Ana - Elhuyar Zientzia

• Softwarea

Some optical signal processing steps can already be performed, for example, using a light beam on the fiber optic transmission network to channel another beam. But complex tasks require logical doors with transistors in silicon chips.

The transistor is a switch that causes any signal to start or stop another signal. In addition, you can amplify this other signal. This last function has been the one that has cost them the most to achieve by optical mechanisms, since the input and output signals are laser rays.

In its new light transistor at the National Institute of Advanced Industrial Science and Technology in Tsucuba, a red laser beam increases 60 times a blue beam. This red ray brings energy to electrons found in silver particles placed on the surface of a normal DVD and moves them like waves. This movement affects the blue beam, just as the waves caused by a ship going in the sea make the boat move next door.

The basic component of the mechanism is the train of pulses of silver particles from the surface of the disk, as it is the deposit of waves that can be put into motion. These light transistors, due to their small size and simplicity, have a low cost, which will allow in short to realize fully optical circuits in miniature.