Author: Marie Hjeltman
Date published: 2024-11-20
Next-generation quantum technologies are set to revolutionize our world, and developing specialized materials is key to making these advancements a reality. In Sweden, the Wallenberg initiatives WACQT, WINQ, and WISE are focused on quantum information technologies and materials, while in Denmark, the newly established Novo Nordisk Quantum Computing Center (NQCP) at the Niels Bohr Institute aims to drive breakthroughs in quantum science.
In the spirit of creating a strong quantum-centric hub in Scandinavia, Nordita is building collaborations between quantum centers, including Nordic Quantum. A year ago, Nordita hosted the Materials for Quantum Technologies workshop to promote these efforts.
Nordita’s Theoretical Quantum Matter Group, led by Prof. Alexander Balatsky, is focused on developing materials crucial for next-generation quantum technologies. In September 2024, Nordita and NQCP launched a joint project focused on understanding the material properties needed for advancing quantum technologies, particularly in superconducting and semiconducting qubits. The collaboration will address key questions in quantum materials science, including:
- How can tailored materials improve the coherence times of qubits?
- What novel materials can be engineered for more stable quantum computingplatforms?
- How can theoretical models guide the development of next-generation quantum devices?
Nordita/TQM postdoc Olli Mansikkamäki explains: “Superconducting qubits, which are built using Josephson junctions, are currently the most common type of quantum computer component. However, a major challenge for quantum computers is decoherence—the loss of the unique quantum properties that distinguish them from classical computers. A primary source of decoherence in superconducting qubits comes from two-level systems (TLS), whose physical origins are still unclear. The goal of this collaboration is to identify what these TLS are and figure out how to eliminate or mitigate the decoherence they cause.
At Nordita, we have developed a novel method called two-tone spectroscopy, which helps detect the influence of strongly coupled TLS on qubits. While this technique can reveal the presence of TLS, it doesn’t explain what causes them. TLS are often believed to exist in the amorphous oxide layers that form the insulating barriers in Josephson junctions. The project is focusing on atomic-scale modeling of these oxide layers to identify potential sources of TLS and comparing different materials to see which ones are more likely to lead to their formation.”
Looking ahead, the collaboration between Nordita and NQCP is set to explore critical questions in quantum materials science, advancing the possibilities in the field. As Nordita’s Director, Mikael Fogelström, puts it:
“By combining expertise from both Nordita and NQCP, this collaboration aims to advance our understanding of quantum materials and improve the performance of quantum technologies.”
