Evangelos Piliouras: Unveiling quantum secrets through collaboration and exploration

This phot shows a young man with black hair, beard, and eyebrows standing at a whiteboard writing equations with a red marker. — Physics graduate student Evangelos Piliouras is fascinated by the challenges and promise of quantum computing. Photo courtesy of Panagiotis Anastasiou.

The following story was written in December 2023 by Nidhi Chopdekar in ENGL 4824: Science Writing as part of a collaboration between the English department and the Center for Communicating Science.

Quantum computers are making waves, challenging everything we thought we knew about computing, and Evangelos Piliouras is determined to overcome the challenges and understand the potential of this new tool.

Delving into the mysteries of quantum bits and the mind-bending possibilities they hold is a fascinating journey, says Piliouras. Unlike classical computers that use bits to represent information in binary code, quantum computers deploy quantum bits, or qubits, which can exist in superposition. This unique property enables quantum computers to perform, potentially offering exponential speedup for certain problems.

Can we harness the power these quantum computers hold? In the domain of quantum research, Piliouras, a Ph.D. student in physics at Virginia Tech, has embarked on a journey to master the art of controlling quantum computers.

Piliouras, with a background in electrical engineering, has found his passion in the theoretical aspects of quantum computers. After studying electrical engineering in Greece, Piliouras went to Saudi Arabia to learn more about electrical engineering but with an emphasis on physics-related courses. His love for quantum computers and classical physics was so strong that he decided to switch from the practical world of engineering to the theoretical world of physics, and he found Virginia Tech to be the perfect place for that.

Piliouras’s fascination with controlling quantum systems arises from the challenge of bridging the gap between theoretical models and unpredictable experimental outcomes. At the heart of his research lies the challenge of uncertainty in quantum systems. Quantum computers are tricky to control because qubits are very sensitive to interactions with their environment and errors in the control parameters, which can even change over time. If we do not adapt to these changes with smart control methods, the quantum computer might not do what we want it to do.

In his quest to control quantum computers, Piliouras is exploring the idea of “robust control,” the ability to maintain a stable performance of systems with disturbances, to manage uncertainties and make sure things go the way we want, even if there are unexpected changes.

For Piliouras, research is not just about advancing technology; it's a quest for a holistic understanding. He isn't just trying to make technology better; he really wants to understand it all. He enjoys figuring out how quantum mechanics works by looking at both theory and experiments. He's not just a hands-on expert or a person who thinks a lot — he's both. This, he says, allows him to connect different pieces of information and tell a complete story in the world of quantum control.

As any quantum researcher would attest, challenges are the spice of scientific life, Piliouras says. He recalls his initial bewilderment when faced with unexpected phenomena in experimental setups. Collaborations with experts from Sandia National Laboratories and external projects like the QSCOUT initiative (Quantum Scientific Computing Open User Testbed, a program that provides access to small testbed quantum computers) provide exciting opportunities to confront and overcome these challenges, turning each hurdle into a learning experience.

Piliouras has already produced encouraging results. His initial findings indicate improved performance, marking a significant step forward for his research.

Piliouras fondly recalls a pivotal moment that defines his journey. As he familiarized himself with the papers in quantum mechanics and the literature surrounding a theory his research group was working on, something clicked. His background in a different field, along with his mathematical training, allowed him to identify structures and elements in equations that had been treated in a specific way by previous researchers and authors. He posed a question to himself: "What if I try something different, just for the sake of my own understanding?"

To his surprise, this led him to uncover something entirely new. Excitedly, he shared his discoveries with a friend and colleague. Both of them then independently arrived at the same results, but with unique perspectives that complemented each other. It was a beautiful moment of synergy, Piliouras says, when their individual routes converged to confirm the validity of their findings.

Piliouras extends advice to other researchers: Be open, be flexible, and, above all, be curious. He has moved beyond the initial challenges associated with understanding the language of quantum mechanics, he says, and his journey now seems smoother. He encourages aspiring researchers to take diverse classes, change departments if needed, and immerse themselves in broader knowledge. Every initial difficulty, he says, will transform into a rewarding experience with time.