Slashdot Mirror
Transistor Made From Bose-Einstein Condensate
holy_calamity writes "US researchers have made a transistor from a Bose-Einstein condensate. They claim it to be the first step towards 'atomic circuits' that run with atoms instead of electrons. 'A small number of atoms can be used to control the flow of a large number of atoms, in much the same way that an FET uses a gate voltage to control a large electric current,' says lead research Alex Zozulya. The abstract of their paper is freely available."
Transistor Made From Bose-Einstein Condensate
Ewwww.....
Libertarian Leaning Political Discussion Forum.
More physics, more chemistry...
Electrons are areas of probability density for energy.
Photons are discrete packets of energy.
Energy is related to mass, most commonly, as E=mc^2.
In conventional circuits there is a signal passed by energy. That energy is passed in bulk as the movement of electricity, or the flux of the electron fields around the atoms which make up the conducting wire.
If one could deal in smaller amounts of energy--say the quanta required to excite an electron from one energy level to the next--then one is dealing arguably in portions of electrons. Arguably.
It's the same principle as the recent research using fiberobtic materials for processor fabrication. If one uses light, rather than electricity, then friction is minimized, energy lost to heat is minimized, and the bulk signal of photon flux can be modulated more quickly than the bulk signal of electron flux.
E=mc^2. It's all the same. You can pass bowling balls or you can pass bee-bees.
the NPG electrode was replaced with carbon blac
Maybe it's determinism or something. Electrons jump tracks and when you speed up your switching rates, meaning you're controlling (and switching on) smaller groups of electrons, you end up with problems with electrons jumping the track. IIRC the DEC Alpha was the first CPU in which this problem cropped up and they ended up making two 45 degree turns in their paths instead of a single 90 degree turn for the first time. This comes at a cost in real estate. Perhaps it would ultimately provide an improvement in overall performance, or at least performance per unit of area.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
With a really, really, really big heat sink.
>>electrons are so much smaller (and hence faster) than atoms
Electrons actually don't flow that fast through a wire. Less than a millimeter per second.
The reason why electricity is so fast, isn't because electrons are fast. It is fast for the same reason that if you have a pipe filled with water, and you start pumping more water in one side, water gushes out the other side immediately a great distance away, even though water isn't flowing through the pipe that quickly. This happens because although the water is slow, the pressure increases along the pipe much faster. Water is more or less incompressible, so pressure on one side of the pipe causes each water molecule in succession to transfer the pressure through it into the next without moving the molecules closer together by much. Thus the water moves almost as a single block, the force itself being only limited by the speed of light (ideally).
Similarly, although electrons are relatively slow to move, the voltage or electric pressure moves through the wire at the speed of light (practically at about 1/3 that speed). It is *this* speed barrier that we are currently running into in computer design, where the slowness of the speed of light over a few centimeters on a mother board will cause the signals in wires to get out of sync if one wire is slightly longer than the other. This happens there because although the voltage is moving incredibly fast, the clock rate of the circuitry is something like a billion oscillations a second. An electric pulse will only move slightly less than 10 centimeters in a billionth of a second.