Photo: Joachim Rode

Vanguard of quantum society

Quantum theory and atomic physics
A new basic research centre at DTU aims to secure Denmark a leading international position in the field of quantum technology. At the same time, the University is advancing interdisciplinary collaboration with a new centre to focus on how the fascinating theories of quantum mechanics are being translated into new technologies.

A hundred years ago, Niels Bohr and a number of other physicists revolutionized our perception of the world. They showed that the natural laws that apply at the atomic level are different to those in classical physics.

“We are now facing another quantum revolution, where quantum mechanics is being translated into a number of new technologies with great practical significance for society,” says Ulrik Lund Andersen, Professor at DTU Physics.

He heads DTU’s new Center of Excellence: the Center for Macroscopic Quantum States as well as the interdisciplinary centre Quantum DTU, which brings together expertise from ten departments across the University. The centre is focusing on quantum sensors and communication, and aims to position DTU as a leader in research and education in the field of quantum technology.

Inexplicable using classical physics
Quantum mechanics challenges our ability to think abstractly. For example, it is generally accepted in quantum mechanics that a particle can be in superposition—that is, in several places at the same time. If you measure its position in an experiment, you will find only one particular position, but this is assumed to be a characteristic of the measurement itself—and does not change the fact that the particle was actually in two or more places at the same time.

Quantum mechanics also allows an atom to be in two different energy states at the same time. Another key element of quantum mechanics is that the elementary particles not only have mass and charge, but also ‘spin’, which cannot be explained using classical physics. In the past, quantum mechanical phenomena have mainly interested physicists, but in recent years engineers have also entered the fray, as a number of practical applications have become apparent.

“For example, computers that exploit quantum mechanics phenomena would be able to solve highly complex tasks that ordinary computers will never be able to solve,” says Ulrik Lund Andersen.

Great potential for Danish industry
Quantum computers are not expected to be a reality for 20-30 years. However, a number of other quantum technologies will be ready before then,” notes Ulrik Lund Andersen:

“At DTU Physics we are primarily working on developing quantum technology that guarantees secure data transfer and quantum sensors that allow extremely precise measurements. We are strong in these two areas, and there is the added advantage that they are both close to the commercial market. This will probably be where we see the first products and new companies based on quantum mechanics.”
Ulrik Lund Andersen notes that the two quantum technologies for secure communication and better sensors are also fundamental to the development of the quantum computer.