Chinese Scientists Just Built A Computer Chip Out of Water

For decades, the story of computing has been inextricably linked to silicon.  Refined from humble sand, semiconductor has powered the digital revolution, its ability to control electron flow forming the bedrock of our modern world. But now, a radical new chapter is being written, one that challenges our very understanding of what constitutes a computer chip.  Chinese scientists from Zhejiang University have achieved the seemingly impossible: they’ve built a functional computer chip using water.

The novelty of this approach is breathtaking.  While silicon’s role in electronics is well-established, the idea of harnessing the properties of water for computation is revolutionary. This isn’t about water cooling; it’s about water being the computational medium.  

This innovation, detailed in a recent publication in the journal Device, leverages the unique properties of water molecules. Using light pulses, the chip exploits the rapid polarization changes of water molecules to generate a signal. This signal propagates through the water, decaying predictably in a natural process that eliminates the need for complex and energy-intensive circuitry found in traditional silicon chips.

To better understand it, think of water molecules as tiny magnets with a positive and negative end. These magnets can be flipped by light, and this flipping creates an electrical signal. The researchers discovered that this signal decays exponentially – like the fading sound of a bell – as it travels through water. This predictable decay is the key to the chip’s operation.

Imagine a line of dominoes (or magnetic dominoes, in this case). If you push the first one, it knocks down the next, and so on. The chip works similarly, but instead of dominoes, it’s water molecules flipping each other’s polarity. The light acts as the initial push, and the signal weakens as it travels down the line of molecules, just like the force of the dominoes diminishes as they fall. This natural signal decay eliminates the need for complex circuitry found in traditional computer chips, making it incredibly energy-efficient.

To simulate how the water molecules behave, the team used a model called the Ising model, often used to understand magnetism. This model helped them predict and understand the exponential decay of the signal. They also built a prototype chip that successfully identified the letters “ZJU,” the initials of Zhejiang University, demonstrating its functionality.

This unexpected breakthrough draws inspiration from the brain itself.  The liquid environment surrounding neurons, where electrochemical signals similarly propagate and decay, served as a biological model for this low-energy, high-performance computing paradigm. Although the brain demonstrates impressive computing power, the biggest advantage of human brain over semiconductor chips is the energy efficiency. While the brain, with its roughly 100 billion neurons and trillions of synapses, operates on a mere 20 watts of power, simulating its functionality digitally requires megawatts. This difference highlights a vast disparity in energy consumption per computational operation.
In fact, current AI systems, like those powering chatbots, consume vast amounts of energy – enough to power a small city in a single day. By contrast, this new water-based chip consumes a mere 10⁻¹⁸ joules per operation – that’s incredibly tiny! Think of the energy it takes to lift a grain of sand a fraction of an inch. This is orders of magnitude less energy than current state-of-the-art computer chips.

While still in its early stages, this water-based chip represents a significant leap forward in low-power computing. Its potential applications are vast, ranging from more energy-efficient AI to advanced robotics and other technologies that currently demand significant power. The use of water, a readily available and sustainable resource, adds another layer of appeal to this promising technology. The researchers are confident that further development will lead to even more powerful and efficient water-based computing systems.