Magnetic logic makes for mutable chips.
Jared Sperli stashed this in science
Software can transform a computer from a word processor to a number cruncher to a video telephone. But the underlying hardware is unchanged. Now, a type of transistor that can be switched with magnetism instead of electricity could make circuitry malleable too, leading to more efficient and reliable gadgets, from smart phones to satellites.
Transistors, the simple switches at the heart of all modern electronics, generally use a tiny voltage to toggle between ‘on’ and ‘off’. The voltage approach is highly reliable and easy to miniaturize, but has its disadvantages. First, keeping the voltage on requires power, which drives up the energy consumption of the microchip. Second, transistors must be hard-wired into the chips and can’t be reconfigured, which means computers need dedicated circuitry for all their functions.
Related stories Solid-state physics: A new spin on spintronics Applied physics: Champing at the bit High-density memory: A switch in time More related stories A research group based at the Korea Institute of Science and Technology (KIST) in Seoul, South Korea, has developed a circuit that may get around these problems. The device, described in a paper published on Nature’s website on 30 January, uses magnetism to control the flow of electrons across a minuscule bridge of the semiconducting material indium antimonide (S. Joo et al. Nature http://dx.doi.org/10.1038/nature11817; 2013). It is “a new and interesting twist on how to implement a logic gate”, says Gian Salis, a physicist at IBM’s Zurich Research Laboratory in Switzerland.
That's a creative use of magnetism. I'm impressed.