Here is a great collection of touch switch circuits. A touch switch is an electronic device that enables us to control a circuit by simply touching a sensor. Simple touch switch circuit with 4011 – ...

In theory, the hundreds of photons, controlled by the triggering photon, could fan out and switch off hundreds of other transistors in an optical circuit.

Transistors are the basic components of electronic circuits and are used in a variety of applications, including electronic switches and current amplifiers.

Each semiconductor transistor can switch on and off billions of times per second. Compared with silicon transistors, the wood transistors are significantly larger, each 3 centimetres long.