Quantum Jitters: Yesterday, I visited my local Apple store to fix an iPhone glitch. It turns out that hanging around for too long in Apple stores is a very bad idea — I was a heartbeat away from handing over my credit card to buy a shiny new iMac. As I played with the touchpad on one of Apple’s beautiful machines, swiping through screens like Tom Cruise in Minority Report, I started to ponder: How will it all end? After all, miniaturization can only go so far, but what’s the limit? Well, it turns out that researchers might have found it.
Moore’s Law dictates that every 18 months, the density of transistors on integrated circuits should double. This is a basic tenet of technology and is the driving miniaturization factor that gives us computers that can fit in our pockets. However, according to researchers at McGill University and General Motors who carried out tests on a microscopic tungsten probe and gold surface interface, when they applied electricity across the interface, the current dropped off far quicker than they predicted. Basically, they had probed the quantum limit of the flow of electrons through the material.
“You could use the analogy of a water hose,” said Peter Grütter, a physics professor at McGill University. “If you keep the water pressure constant, less water comes out as you reduce the diameter of the hose. But if you were to shrink the hose to the size of a straw just two or three atoms in diameter, the outflow would no longer decline at a rate proportional to the hose cross-sectional area; it would vary in a quantized (‘jumpy’) way.”