Working in Quantum. Insights and behind-the-scenes with ParityQC’s Christian Ertler
Our Working in Quantum interview series puts the spotlight on the people that are part of the flourishing quantum computing industry. Our fifth interview is with Christian Ertler, Head of technology partnerships and senior quantum scientist at ParityQC. Christian worked for years at the intersection between the research, business and political side of quantum computing, and he took a leading role in communicating its potential. In this interview, he talks about how he became fascinated in physics, his work at ParityQC and our newly launched projects in Germany. He also gives some insightful advice on the right way to communicate quantum computing to outsiders and how to pick the right company where to do valuable and inspiring work.
What’s your role at ParityQC?
I am responsible for coordinating our technology partnerships in Germany and managing the technical and scientific aspects of our projects there.
When did you first become fascinated in quantum computing?
When I was in high-school I read the book “Die Evolution der Physik” by Albert Einstein and Leopold Infeld. It is really readable for everyone and despite the statement of the authors: “this book is nothing else than an unpretentious chat”, one gets a really good feeling of how physicists struggle to get a deeper understanding of nature. I was fascinated by the ideas of modern physics from thereon and it was really exciting to learn more and more about it over the years. Especially the deep connection between information and laws of nature is fascinating. Luckily, this journey is still ongoing for me.
How was the career path that eventually led you to ParityQC?
After my PhD, focused on finding novel ways to solve the mathematically challenging Boltzmann transport equation, I worked in several research groups on quantum dynamics and transport in open systems such as magnetic semiconductors, graphene quantum dots or topological insulators. In the following years I switched more to the managing side, taking care of research projects on energy research at the German Aerospace Center. At ParityQC, I could perfectly combine my passion for quantum physics and my joy to manage and bring forward projects in collaboration with others.
If you were to start your studies all over again and could pick any subject and any specialisation, what would it be?
Personally I am most impressed by generalists, and physics at least claims to give a general perspective on nature. Since the field is so large at some point one has unfortunately to specialise. One one hand I am really happy with my choice, on the other I still regret to never have a deeper dive in many fascinating fields of nature, e.g., to understand how life is possible and how it works on the microscopic level.
For a long part of your career, you were working between the research, the business and the political side of quantum computing. What motivated you when communicating quantum computing, sometimes to outsiders? I assume a true belief in its importance and potential is essential.
Indeed, an authentic personal passion for it is the most important precondition to convince other people, e.g., in politics or business. The developed theoretical concepts and the things we can do nowadays with single atoms or tailored nanostructures are really impressive. At the same time it is important not to overpromise, which one could do by withholding the significant challenges we still face in making robust quantum information processing a reality. Only both passion and a realistic and honest view on QC can provide a long-term sustainable support by politics and the society.
What are you busy with right now?
Recently we kicked off a lot of our fascinating German projects, in which different hardware platforms, e.g., based on trapped ions, neutral atoms, or superconducting qubits will be scaled up. In these projects we are collaborating with lots of partners and I am currently building up our cooperations to tackle the first pending tasks.
In what ways do you think ParityQC stands apart from other quantum computing companies?
ParityQC provides a complete architecture for solving general optimisation problems. As a result, our compiler specifies the concrete geometric arrangement and the needed local couplings of the qubits. The concept is truly unique, and through the co-design of algorithms and coupling gates, the best performance for different hardware platforms can be obtained. To work on this direct interface between hardware and algorithmic development is really great fun and it allows you to broaden and deepen your knowledge on all the different promising qubit candidates and quantum algorithms.
Quantum computing could have an impact on so many industries, which ones are you most looking forward to seeing? In your career you’ve also dealt with technology for renewable energy, could quantum computing help the advancement of this field?
As optimization problems are omnipresent, almost all industries would strongly benefit from functioning quantum computers. Personally I think that, as a first application, improved understanding of complex chemical reactions and complex molecular structures by quantum simulation would really help to develop better and maybe even personalised drugs.
Indeed, the strongly interconnected energy system with a high share of fluctuating renewables and decentralised power units is a highly complex system. Hence, global system optimisation is key to decrease the total CO2-emissions and costs and to secure the systems stability and resilience. There are already first approaches to solve the so-called unit commitment problem on quantum computers.
What inspires you to come to the ParityQC office (or log in) every day?
Clearly at the first place all the congenial and sympathetic people at ParityQC, which are all very passionate about their work. It is just fun to discuss and to solve problems together with them. I am also strongly motivated by the aim to make the ParityQC Architecture a reality on different hardware platforms, exploiting all of its advantages and enabling the solution of significant real-world problems – which is the thing that ultimately matters from a computational perspective.
Do you have some final advice for someone just starting out in this sector?
It is really a great time for people who are fascinated by the connection of quantum physics and computer and information science. There are now a lot of possibilities to earn a good living with things you really like to work on. My advice is that you have a close look at the aims of the company of your choice questioning yourself if you consider them to be realistic and if you can learn there from really excellent people. In that way you will gain a deeper and broader knowledge which will open many doors for you in the future.