A team of scientists has found a clever new way to make quantum measurements faster without losing accuracy—a big step forward for quantum technologies like supercomputers and ultra-secure communications.
Quantum systems, unlike regular computers, use qubits instead of bits.
These qubits can exist in several states at once until they’re measured, thanks to a strange quantum rule called superposition.
But measuring a qubit accurately has always been tricky. The longer you measure, the more accurate your result—but waiting too long can lead to errors because quantum systems are delicate and easily disturbed.
Until now, scientists believed they had to make a trade-off: either get a fast measurement or an accurate one, but not both.
However, researchers at the University of Bristol and their partners have changed the game.
Their new method allows for quick and reliable quantum measurements by adding more qubits to the process.
Chris Corlett, a PhD student at Bristol’s School of Physics and the lead author of the study, explained the idea with a simple analogy. Imagine you’re shown a picture of two glasses—one with 25 milliliters of water, the other with 20.
If you only look at the picture for a second, it’s hard to tell which glass holds more. But if the glasses were bigger—say, 50 and 40 milliliters—it would be easier to tell the difference in the same short time.
Corlett said that’s basically what their new method does. By adding an extra qubit, it’s like increasing the “volume” of information in each measurement. This allows the system to reach an accurate result more quickly. And the more qubits you add, the faster and more confident the measurement becomes.
Working with his supervisors—Prof. Noah Linden and Dr. Paul Skrzypczyk—as well as experts from the University of Oxford, Strathclyde University, and Sorbonne Université in Paris, Corlett developed this new approach. The findings were published in Physical Review Letters, a leading scientific journal.
What’s especially exciting is that this method doesn’t just maintain the quality of a quantum measurement—it can actually make it better, even as it speeds things up. That’s a rare achievement in quantum research, where improvements in one area often come with setbacks in another.
This new technique could be used across many types of quantum computing systems, helping scientists and engineers build more powerful and reliable quantum devices.
As the race to develop practical quantum technologies heats up worldwide, this breakthrough could become a standard tool in the quantum toolbox.
Source: University of Bristol.
