All-optical transistor could be a big leap for quantum computing

Researchers at MIT, Harvard and the Vienna University of Technology have developed a proof-of-concept optical switch that can be controlled by a single photon and is the equivalent of a transistor in an electronic circuit. The advance could improve power consumption in standard computers and have important repercussions for the development of an effective quantum computer.

Chip manufacturers are constantly pushing to reduce power consumption to a minimum, but they still have to face the limitations that come with dealing with the world of electronics. In particular, the power consumed by a CPU is roughly proportional to its frequency and the square of its voltage, with a good portion of the consumed energy being dispersed as heat.