Scientists spin diamonds at a billion RPM to test the limits of physics Premium

Fluorescent nanodiamonds (FNDs) revolutionize various sectors with unique properties, including stable fluorescence and potential quantum applications.

As scientists’ understanding of the basic properties of matter has improved over time, they have been able to engineer materials with the best properties for specific applications. Such bespoke materials have revolutionised various sectors, including medical diagnostics, spaceflight, cryptography, commercial electronics, and computing. One such material is the fluorescent nanodiamond (FND).

FNDs are nanometre-sized diamonds made of carbon nanoparticles. They are produced in a high temperature and high pressure process. FNDs are stable under light and aren’t toxic to living things, so they have many applications in high-resolution imaging, microscale temperature sensing, and correlative microscopy, among others. In biology, scientists use FNDs to track cells and their progeny over long periods.

Fluorescence is the property of some materials to emit light of lower frequency when irradiated with light of a higher frequency. But unlike many other nano-scale fluorescent materials, FNDs don’t blink when irradiated for a long time. Their fluorescence lifespan is greater than 10 nanoseconds (ns) — a relatively long duration — which makes them better than quantum dots, whose inventors won the chemistry Nobel Prize last year.

In a recent study published in Nature Communications, physicists from Purdue University in the U.S. reported levitating FNDs in a high vacuum and spinning them very fast. It sounds like a simple, even comical, feat but is actually quite difficult. And now that it has been successfully demonstrated, it paves the way for multiple applications in industry, especially as sensors, and in fundamental research.

One of the basic features of the building blocks of matter, like electrons and nuclei, is a property called spin. At any given moment, its value is a combination of two states called up and down. For a simplistic illustration, the spin of an electron can be 30% up and 70% down. If the down component is zero, the spin will be up, and vice versa. A computer can map these values to 0s and 1s and use the electrons to encode information. This is how a magnetic hard drive in a computer stores your data.

When a quantum computer manipulates the spin of some particles to perform its operations, each particle is called a spin qubit of the computer.

The Purdue University team made some FNDs and spun them at an ultra-fast rate, making multiple notable findings.