Quantum Research
By Chance Into the Future
The Hedy Lamarr Quantum Communication Telescope at the roof of the Academy’s Quantum Institute in Vienna.
No coincidence: in a world that is increasingly shaped by codes, algorithms, rules, and agreed objectives, unpredictability does not seem to have much of a future. But this impression is deceptive – chance is preparing its next victory, in quantum physics research and likely soon in everyday life. Quantum researchers from the Austrian Academy of Sciences are playing a key role in this.
PHOTO: KLAUS PICHLER/AUSTRIAN ACADEMY OF SCIENCES
Chance already had a big moment over 100 years ago. Around 1900 the physicist Max Planck introduced the idea of quanta. From the beginning, quanta – particles that assume an infinite number of states simultaneously and that are only randomly assigned to a state when they are measured – appeared as controversial as they were promising.
Controversial, because even thinkers like Albert Einstein had trouble with the idea of quanta and the quantum mechanics that emerged in the 1920s with its putative paradoxes: “God does not roll dice,” he once said, trying to put chance in its place. And promising, because that was exactly what did not happen. “One of the most fundamental realizations in quantum physics is that there is pure coincidence,” the Austrian quantum physicist Anton Zeilinger says. “So, there are individual events that have no underlying cause,” continues Zeilinger, who has also been President of the Austrian Academy of Sciences since 2013.
Schrödinger’s cat is from Austria
What at first glance appears to be a serious disadvantage compared to classical physics, with its predictability and precision, soon opened up potential applications undreamt-of in quantum physics. Using, among other things, probability calculations, quantum mechanics was not only able to predict the general behavior of particles in a surprisingly reliable statistical manner but also drastically increased our understanding of the behavior of the smallest particles. Without the quantum physical revolution in the first half of the 20th century, the technical achievements of the second half, such as lasers, superconductors, and cell phones, would have been unthinkable.
Physicists from Austria were involved in this revolution at an early stage and included Einstein’s contemporary Erwin Schrödinger, who was a member of the Academy. With “Schrödinger’s Cat” – the metaphor of a cat locked in a box, which is at the same time alive and dead until the box is opened – he created the most famous quantum-physical thought experiment to this day.
The quanta are haunted
Austria and the Austrian Academy of Sciences continued this tradition at the end of the 20th century with steadily growing commitment. Thereby, researchers working with Anton Zeilinger have made great strides in studying so-called quantum entanglement. Here, particles are generated with a random but identical direction of oscillation and sent in different directions. The actual direction is undetermined until it is measured on one of the two entangled particles. If that happens, not only the state of this particle but also that of the partner particle, which can be any distance away, is determined randomly but identically – a phenomenon that Albert Einstein once described as “spooky action at a distance”.
Researchers in the quantum lab at the Academy’s Vienna institute.
PHOTO: KLAUS PICHLER/AUSTRIAN ACADEMY OF SCIENCES
Quantum entangled from the blue Danube to space
Whether spooky or coincidence, Austrian quantum physics kept at it and expanded the entanglement between paired particles over the Danube, later over the historic inner city of Vienna, and finally even into space. In 2003, the Austrian Academy of Sciences consolidated the vitality of this research field with the establishment of the Institute for Quantum Optics and Quantum Information, which today has two locations, in Vienna and Innsbruck. Soon becoming one of the top addresses in international quantum research, scientists there have created a furor in several areas of quantum physics, from radically new approaches to quantum information processing by Peter Zoller’s team, to Francesca Ferlaino’s experiments with ultra-cold quantum matter.
While in Vienna, among other things, one global record after the other was set in quantum entanglement, in Innsbruck milestones were repeatedly achieved in another area within quantum physics: in research on quantum computers. The key aspect here: while the smallest processing units in conventional computers are either 0 or 1, so-called qubits in quantum computers can be a combination of both. As a result, qubits can carry out several computing processes in parallel, which brings the computation capacities of a quantum computer system into another dimension. Industry has long since become aware of this high technological potential and is investing billions in research into quantum computers worldwide.
Quantum computers made in Austria
At the Austrian Academy of Sciences, basic research is lived, and applied research considered at the same time. In the field of quantum computers, this is demonstrated by Alpine Quantum Technologies (AQT), a spin-off from the Academy and the University of Innsbruck. The goal of the start-up is to develop a first, commercially usable quantum computer in the coming years.
The basis is the know-how and the technical milestones that quantum researchers at the Academy, among others, have achieved in this area in recent years. “We might not have the infrastructure and money that big corporations have. But we have very good people and we have ideas,” Rainer Blatt says, a quantum physicist at the Academy and AQT co-founder. Quantum entanglement also has the best chance of reshuffling the cards of our digital coexistence: the first intercontinental quantum communication connection established in 2017 between the Academy in Vienna and the Chinese Academy of Sciences in Beijing showed that the entanglement of light particles with the help of orbiting satellites enables completely tap-proof data transfer. The randomly generated cryptographic quantum key was transmitted to the sender and recipient of a data packet and at the same time secured by quantum physical laws – any attempt at eavesdropping would have been exposed immediately. With this proof of concept, a central basis for the quantum internet of the future was created.
The fact that science leaves much to chance would probably have surprised researchers in the past. For the quantum physicists at the Austrian Academy of Sciences, however, this is part and parcel of their experiments and studies. And their success proves them right.
Quantum physicist and Academy president Anton Zeilinger with a model of the satellite “Micius” during the world’s first intercontinental quantum video-call in 2017.
PHOTO: DANIEL HINTERRAMSKOGLER/AUSTRIAN ACADEMY OF SCIENCES
Q&A with Anton Zeilinger, quantum physics pioneer and President of the Austrian Academy of Sciences.
How is Austria positioned internationally in quantum physics?
In terms of output, despite our small size, we are one of the best positioned countries in the world.
Quantum physics promises numerous future applications – keyword: quantum internet. Why is it still important to do basic research?
The really new thing that tomorrow’s world needs will come from basic research, because good basic research is driven solely by curiosity and therefore comes across things that no one has thought of before.
What do you find fascinating about quantum physics?
The beauty of the mathematics and the fact that many findings from quantum theory contradict our everyday experience.
What new scientific discoveries have you recently come across?
We have succeeded in teleporting multidimensional quantum states, which will enable future quantum computers to have higher information capacities than with conventional qubits.