Renowned scientist James Clerk Maxwell had a peculiar thought almost 150 years ago. He wondered what would happen if you could be able to see a system so closely and accurately, all of its minute details, that could see every tiny fluctuation as moved due to the or water molecules around it. Maxwell wondered if those fluctuations could be used to convert them into work.
This random 150-year-old idea has led a group of scientists from the Simon Fraser University or SFU to develop an unusual engine that is able to convert information into work. This information engine is based on Maxwell’s idea and works by taking information as a fuel to generate energy. The engine basically works by detecting and reacting to the motions of particles in order to achieve perpetual motion (in theory).
The senior author of the study, physics professor John Bechoefer from SFU explained that “That’s the kind of information that we’re using. We wanted to find out how fast an information engine can go and how much energy it can extract, so we made one”. So the theory behind their engine is a little too technical even for me but I’ll try my best.
The information engine is basically a tiny microscopic particle bead immersed in water. The bead is somehow attached to a spring that is in turn attached to a movable stage. Now since the bead is microscopic, it can’t be attached to a spring. So scientists employed a workaround here by using an optical trap. They used a laser in order to create a force on the bead which imitates the movement of the spring and the stage.
The thermal motion from the laser causes the particle to bounce up and down. This technique plays the role of Maxwell’s demon which is basically another name for information engine. Maxwell’s idea considered a demon that controls a door between two gas chambers, with the goal of sending fast-moving gas particles into one compartment and slow ones into another.
The scientists then imitated the movement of the particle with the movable stage and by repeating this action they stored a good amount of gravitational energy. According to Ph.D. student Tushar Saha, “This ends up lifting the entire system using only information about the particle’s position”.
The information was able to generate enough power to mimic molecular machinery in living cells with speeds comparable to fast-swimming bacteria. The biggest achievement here is that their design outperforms other similar engines by an order of magnitude higher.