Quantum Computing Technologies Group

Quantum Computation (QC) is arguably the most revolutionary of all new quantum technologies, as it may transform many industrial sectors with a direct impact on society. In the past five years, the field has experienced a huge transformation as it is being adopted and developed by industry after two decades being an almost purely academic endeavor.

There exist today small-scale prototypes produced by both research groups and large corporations. Those devices are getting powerful enough to provide advantages over conventional computers in specific applications. However, in order to achieve the long-sought “quantum supremacy”, several key developments are still necessary.

IFAE is fully engaged in this technology since 2019. The particular implementation developed at IFAE, quantum annealing, is one of the most promising avenues by which to achieve an advantage over conventional computers by solving optimization problems which are ubiquitous in society (delivery, traffic, chemistry, etc.).

The QCT group develops superconducting circuits for applications in quantum computation. By employing Josephson-junction technology, the group engineers superconducting qubits for the implementetion of quantum algorithms. Part of the research is focused on improving the qubit quality by mitigation of environmental noise sources, while at the same time the circuits are used to investigate fundamental physics of quantum optics phenomena.

Refrigerator at the IFAE QCT Lab Credit: IFAE QCT Group

In 2020, the QCT group achieved the complete construction of its laboratory at the IFAE workshop. The new laboratory was already used to complete the first complete work performed at IFAE, the demonstration of a single qubit as a universal approximant. This new quantum algorithm was deviced by the group led by Prof. J. I. Latorre, currently the director of the Center for Quantum Technologies in Singapore, and was implemented using the single superconducting qubit device that was fabricated by the group of Prof. Martin Weides at the Karlsruhe Institute of Technology. The initial round of measurements had been performed at the Catalan Institute of Nanoscience and Nanotechnology (ICN2) in the lab of Prof. S. O. Valenzuela while the IFAE laboratory was being built. This quantum algorithm uses the qubit properties to approximate the value of any bounded mathematical function after a series of quantum gates applied to the qubit. The experimental demonstration showed full agreement with the simulated values. A preprint was produced in early 2021.