By Josh Perry, Editor [email protected]
In the 1960s, Rolf Landauer described a theoretical lower limit for the amount of energy required to erase one bit of information (from the 1 state to the 0 state), but University of Twente scientist Jan Klaers has proposed that synchronizing computer operation and temperature to reduce the energy below the limit that Landauer devised.
A new theory proposes a method for cooling computers below Landauer’s limit. (Wikimedia Commons)
According to a report from the university, “Looking at the many logical operations that take place in a computer, the temperature profile is complex. If one bit changes state at a certain logical gate, the temperature change will be ‘felt’ in the surrounding gates as well. Although complex, the temperature and energy consumption have the same rhythm as the clock of the microprocessor.”
Klaers theorized that it would be possible to synchronize logical operations for the squeezed thermal states where temperature and energy costs are both lower, which would reduce energy consumption below Landauer’s limit.
“For this, Klaers analyzed a minimalist mechanical model resembling the one Landauer used for his theory, representing a one-bit memory,” the article continued. “These are the fundamental basics: further research will have to show what results can be achieved in actual computer systems.”
The research was recently published in Physical Review Letters. The abstract said:
“Landauer’s erasure principle states that the irreversible erasure of a one-bit memory, embedded in a thermal environment, is accompanied with a work input of at least kBTln2. Fundamental to that principle is the assumption that the physical states representing the two possible logical states are close to thermal equilibrium.
“Here, we propose and theoretically analyze a minimalist mechanical model of a one-bit memory operating with squeezed thermal states. It is shown that the Landauer energy bound is exponentially lowered with increasing squeezing factor.
“Squeezed thermal states, which may naturally arise in digital electronic circuits operating in a pulse-driven fashion, thus can be exploited to reduce the fundamental energy costs of an erasure operation.”
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