Light-Emitting Particles Yield Faster Computing

schliz writes to tell us that researchers at the University of California San Diego are developing new transistors based on particles called 'excitons' in an attempt to speed up the interaction between computing and communications signals. "Excitons are formed by linking a negatively-charged electron with a positively-charged 'hole'. An exciton decays when the electron and hole combine, emitting a flash of light in the process. By joining exciton-based transistors to form several types of switches, the UCSD physicists were able to achieve switching times on the order of 200 picoseconds."

Comments

Vacuum tubes

[bluefoxlucid]

My guitar amp works on vacuum tubes. Basically, the negatively charged cathode emits electrons when heated, creating a "space charge" in the area. In the recto tube (responsible for the characteristic "Sag" effect due to reaction delays when current demand jumps) this floats across to the positively charged anode and gets siphoned away; in a triode or beam tetrode or pentode or whatever else, a grid manages the flow.

I've used a MOSFET as a source follower, the source being the negative source of course, to supply current flow to the Baxandall tone stack. Basically, the MOSFET has a positively doped channel, and a negatively doped source and drain. The source and drain contain many electrons, while the channel contains holes. Applying a charge to the grid causes P material to form an N channel allowing electron flow. In a P channel MOSFET this works the other way. (it's hard for me to explain this, the above is likely wrong)

In a BJT, an NPN has two negative electron-filled materials and a P material filled with holes. A PNP has two areas of holes, and one of electrons.

A silicon diode uses a region full of electrons (anode), and a region full of holes (cathode).

Guess what? Everything works on electrons and holes (holes don't move)!