Consider a Nanoelectromechanical relay. These are usually used for RF switching so switching voltage isn’t important, but switching voltage can be brought arbitrarily low. Mass of the cantilever determines frequency response. A NEMR with a very long light low-stiffness cantilever could respond well at 20khz and be sensitive to thermal noise. Adding mass to the end makes it less sensitive to transients (lower bandwidth, slower response) without affecting switching voltage.
In a NEMS computer there’s the option of dropping (stiffness, voltage, operating frequency) and increasing inertia (all proportionally) which allows for quadratic reductions in power consumption.
IE: Moving closer to the ideal zero effective resistance by taking clock speed to zero.
The bit erasure Landauer limit still applies but we’re ~10^6 short of that right now.
Caveats:
NEM relays currently have limits to voltage scaling due to adhesion. Assume the hypothetical relay has a small enough contact point that thermal noise can unstick it. Operation frequency may have to be a bit lower to wait for this to happen.
Consider trying to do the reverse for computers. Swap copper for saltwater.
You can of course drop operation frequency by 10^8 for a 10-50 hz clock speed. Same energy efficiency.
But you could get added energy efficiency in any design by scaling down the wires to increase resistance/reduce capacitance and reducing clock speed.
In the limit, Adiabatic Computing is reversible because in the limit, moving charge carriers more slowly eliminates resistance.
Thermal noise voltage is proportional to bandwidth. Put another way if the logic element responds slowly enough it see lower noise by averaging.
Consider a Nanoelectromechanical relay. These are usually used for RF switching so switching voltage isn’t important, but switching voltage can be brought arbitrarily low. Mass of the cantilever determines frequency response. A NEMR with a very long light low-stiffness cantilever could respond well at 20khz and be sensitive to thermal noise. Adding mass to the end makes it less sensitive to transients (lower bandwidth, slower response) without affecting switching voltage.
In a NEMS computer there’s the option of dropping (stiffness, voltage, operating frequency) and increasing inertia (all proportionally) which allows for quadratic reductions in power consumption.
IE: Moving closer to the ideal zero effective resistance by taking clock speed to zero.
The bit erasure Landauer limit still applies but we’re ~10^6 short of that right now.
Caveats:
NEM relays currently have limits to voltage scaling due to adhesion. Assume the hypothetical relay has a small enough contact point that thermal noise can unstick it. Operation frequency may have to be a bit lower to wait for this to happen.