‘Quantum physicists don’t carry out experiments using poor Schrödinger’s cat’

15 Apr 2020

Dr Fabian Laudenbach. Image: AIT

Dr Fabian Laudenbach of the Austrian Institute of Technology tells us why the theory of Schrödinger’s cat might not be the best way to explain quantum physics.

Dr Fabian Laudenbach received his PhD in quantum optics and quantum information from the University of Vienna in 2019. Since 2014, he has been with the Austrian Institute of Technology (AIT) where he is now a staff scientist.

His fields of expertise are experimental and theoretical quantum information and quantum optics.

‘My team and I are trying to exploit the weird phenomena of the quantum world for useful applications in our everyday life’

What inspired you to become a researcher?

I don’t think there was any particular event that sparked my interest in science. I just wanted to understand how the universe works and felt dissatisfied with what I learned about it in school.

I decided to study physics, one thing lead to the other, and now I find myself exploring quantum physics for a living and I couldn’t be happier.

Can you tell us about the research you’re currently working on?

My team and I are trying to exploit the weird phenomena of the quantum world for useful applications in our everyday life. For instance, we are really good at using optical quantum states to establish virtually unhackable encryption. This absolute communication security is something only allowed for by quantum mechanics.

Currently, one of our main goals is to make quantum technologies more available to the broad public. In order to do so, we are striving to develop quantum devices that can be produced in large quantities at low cost.

In your opinion, why is your research important?

Well, to begin with, I think that any research enriches human knowledge and is therefore important by definition; no matter if it’s ground research or application-oriented. As for quantum technologies, I am positive they will have a profound impact on society once they are mature enough.

They can open so many doors in various aspects of life and technology, including communication security, diagnostics and new pharmaceuticals, ecology and strategies against climate change, biogenetics, material design, logistics and many others.

What commercial applications do you foresee for your research?

To name one commercial application we already have, quantum-cryptography devices are already on the market. Another technology based on quantum mechanics is called quantum sensing.

These quantum sensors can measure physical quantities with unprecedented accuracy. This will have huge implications for a lot of industrial and medical applications. The third branch of quantum technologies is quantum computing.

This is certainly the least mature technology yet, and there are still many years of scientific progress needed before we will see actual quantum computers outperforming conventional machines at useful tasks.

But at the same time, it is also the quantum-technology branch that we expect to have the most transforming impact on society with a plethora of applications available.

What are some of the biggest challenges you face as a researcher in your field?

The main challenge is probably exactly what you would guess: quantum-information carriers are usually tiny, extremely sensitive and difficult to control, manipulate and measure reliably. But then again, we are continuously getting better at it.

My group is working with photons, which are fortunately more robust than matter-based quantum systems like atoms and electrons, and we have extremely advanced lab devices available that allow us to work with them.

Are there any common misconceptions about this area of research?

There is a misconception in trying to describe this field by putting animals in boxes and forcing them into a state of half-alive-half-dead.

Quantum physicists do not carry out this type of experiment using poor Schrödinger’s cat. This thought experiment has not been considered as very insightful and actually tends to lead people to a wrong concept about quantum mechanics.

I would even dare to say that, most probably, the public at large would have a better understanding of quantum physics and its beauty if this cat were not used as the main argument of the field.

What are some of the areas of research you’d like to see tackled in the years ahead?

If I could wish for one thing, I would like to see fully-fledged universal quantum computers in action one day. And if I could wish for a second thing, I would like to be part of this breakthrough.

Are you a researcher with an interesting project to share? Let us know by emailing editorial@siliconrepublic.com with the subject line ‘Science Uncovered’.