Technical University Of Denmark Research Finds Quantum Sensors Can Offer Completely New Opportunities

Quantum physics is not new, but we have only recently become able to control quantum phenomena and thus use them to develop new technologies. One of the areas in which quantum technology is most mature and ready for application is quantum sensors, where quantum phenomena can help make the sensors ultra-sensitive, enabling them to see details and measure much smaller quantities than possible with currently existing sensors.

Defective diamonds as quantum sensors
Alexander Huck is one of the DTU researchers who have been conducting research into the use of diamonds as quantum sensors for more than ten years. These are artificial diamonds with a built-in defect: the NV centre. The NV centre behaves like a quantum mechanical spin that can register weak magnetic fields and other physical parameters.
Alexander Huck has used quantum diamonds to measure biological material, among other applications. In 2020, he demonstrated—together with a multidisciplinary research team—that it was possible to measure electrical activity in muscles using an NV diamond quantum sensor.

“The advantage of using diamonds to measure biological material is that we don’t need to attach electrodes to the material to measure a signal. Instead, we can place a diamond, in this case in the shape of a small flat plate measuring 1-2mm x 1-2mm, close to the biological material without ‘damaging’ it and then measure signals using magnetic fields. We’ve recently succeeded in performing similar measurements of brain activity from tissue in mice, which is a major new milestone,” says Alexander Huck, Associate Professor at DTU Physics.

In his opinion, quantum sensors will play a big part in the work to gain more knowledge about the brain and neural networks, eventually contributing to both improved diagnosis and cures for brain disorders.

Knowledge of molecules and photosynthesis
Alexander Huck has recently also started using NV diamond sensors on length scales much smaller than cells and tissue from muscles and the brain. He wants to try using the quantum sensor to gain greater knowledge about molecules. The overall focus is on electronic processes on a molecular scale, such as photosynthesis, which he wants to learn more about by looking at one or a few molecules at a time.

“If we can understand how photosynthesis works in detail, it may—in the long term—allow us to copy how plants harvest energy from the sun and convert it into storable and transportable chemical substances. Much of our current knowledge is based on analyses of large groups of molecules, and this can obscure some of the details. I want to gain knowledge about them by looking at the molecules individually,” says Alexander Huck.