Landauer's theorem relies heavy on the rules of equilibrium thermodynamics. The assumption in equilibrium thermodynamics is that every action starts from an equilibrium state, ends at an equilibrium state, and that we don't care too much about what happens in the middle. This experiment appears to rely on non-equilibrium thermodynamics, where we no longer assume that we start and end at equilibriumEdit: my first answer was wrong.
They explicitly mentionWhat this in the middle of the paper. They focus on actions which can appears to be done faster than the relaxation time of the system. By doing this, they developis creating a structurereversible element which is physically reversible butbeing treated logically irreversibleas an irreversable OR. They do mention that if Because the systemelement itself is permitted to reach equilibrium, the circuit enters a state which "erases" the information. If this happenedreversible, I do believe their MEMS element would be subject to the same energy costs thatit can easily avoid Landauer's principle predicts. However, by making sure the logical measurements occur faster than that, they can stay within the realm of non-equilibrium thermodynamics and yield a more reversible logic element.
As best as I believe this is sidestepping Landauer's principle simply by focusing on non-equilibrium states. This is not an unreasonable approach. It reminds me highly of the famous paper suggesting that bumblebees cannot fly, because a static analysis of their body and wingspan says that they don't have enough lift to fly. Of coursecan tell, everyone knew this had to be false, because we know bumblebees do indeed fly. It tookhas been known for a while before we found out that they were usinglong time: you can have a dynamic approach to flycombination circuit of reversible logic, creating vortexes with their wings which hadand you only pay the effect of amplifyingenergy cost for the effectiveness of their wings. The dynamic effects permit a bumblebee to fly using far less material than they would need to fly using simpler lawsmeasurements taken at the end of flight. Likewisethe process (which must latch, this experiment appears to use dynamic effectsso are subject to use far less energy than would be needed using simpler laws of computationLandauer's principle).