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Landauer Limit Demonstrated


Scientists show that a 50-year-old principle limiting future CMOS computing is real: Erasing information gives off heat


Physicists in Europe have experimentally demonstrated, for the first time, that a theoretical principle limiting modern-day computing is real.In 1961, Rolf Landauer posited that the act of erasing a bit of information gives off an amount of heat related to the temperature and Boltzmann’s constant—a total of 3 x 10^-21 joules at room temperature. Among other things, the theory has been used to address the famous problem of Maxwell’s Demon, a thought experiment that suggested a minute monster could create energy for free by sorting particles by their speed, in apparent violation of the laws of thermodynamics. Prior to 1982, when IBM’s Charles Bennett applied Landauer’s theory to the problem, the thinking was that the demon’s act of making measurements produced heat, eliminating the violation. But Bennett argued that heat was produced because the demon had to erase a bit of information in its memory in order to sort each particle.


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“This is beautiful experimental work,” says IEEE Fellow Mark Lundstrom, a professor of electrical and computer engineering at Purdue University and an expert on the limits of nanodevices. “It’s remarkable that Landauer’s gedanken [thought] experiment can now actually be done.”


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Lees verder: http://spectrum.ieee.org/computing/hardwar...it-demonstrated


Bron: IEEE Spectrum