International Centre for Theoretical Physics contributes to the second quantum revolution


The Abdus Salam International Centre for Theoretical Physics (ICTP) is contributing to a European Commission intitiative aiming to boost the Second Quantum Revolution, exploiting the enormous advancements in our ability to detect and manipulate single quantum objects. ICTP is a driving force behind global efforts to advance scientific expertise in the developing world. Although operating with significant autonomy, the programmes of this institute are an integral part of the UNESCO Natural Sciences Sector programme.

The Quantum Flagship will fund technologies that are based on the laws of quantum mechanics, which govern physics at the atomic scale, with a budget of €1 billion. Marcello Dalmonte of ICTP's Condensed Matter and Statistical Physics section is co-principal investigator of a research project that will focus on quantum simulation, one of five of the Quantum Flagship's research themes, for the first three-year phase of the Flagship. Quantum simulators study quantum systems, such as the atomic make-up of materials or chemical reactions, performing tasks that are too complex for the most powerful, transistor-based classical computers.

The classical computer's quantum cousin, the quantum computer, can perform the same tasks as a quantum simulator, but at a much grander scale. Quantum simulators hone in on very specific classes of problems, without the need for building a complex quantum computer, and so have less-demanding requirements, according to Dalmonte, "The idea of a quantum simulator starts from the fact that building a full-fledged quantum computer is a tough business", explains Dalmonte. "Can we solve meaningful problems with a machine that is not as complex as a quantum computer? That is the idea behind quantum simulators".

Studying the quantum characteristics of materials and chemical reactions could potentially lead to the design of new materials that could revolutionize such sectors as energy and transport, as well as lead to the design of new drugs. Dalmonte and colleagues from the University of Padua are teaming up for their part of the project, joining an international consortium of research groups contributing to the overall quantum simulation stream, known as PASQuanS (Programmable Atomic Large-Scale Quantum Simulation). The EC has granted PASQuanS a three-year budget of just over €9 million.

PASQuans brings theorists and experimentalists together in the quest to advance quantum simulators. Dalmonte is investigating the theoretical side, applying what is known about the behavior of atoms at the quantum scale to benchmark, verify, and potentially certify the functioning of such machines. "We are interested in questions like, how can we check if the simulators are properly working or not? Can we benchmark them in systematic ways? We are working on a series of theoretical aspects which are, most of the times, completely open, because these machines are relatively new."

Dalmonte admits that a full solution to these problems is beyond the scope of the three-year Quantum Flagship starting grant, however he believes that they could achieve a set of diagnostics that could be used to verify and, in some cases, certify quantum simulator results. "This allows us at ICTP to have an immediate connection channel to a lot of top-level experiments, which I believe in this field is really fundamental."