Nobel Prize winner visits CERN’s superconductors

On Wednesday 23 April Georg Bednorz, who won the Nobel Prize for physics in 1987, visited CERN along with 44 of his colleagues from the IBM Zurich Research Laboratory.

Georg Bednorz (second from right) with colleagues from the IBM Zurich Research Laboratory in the LHC tunnel.

On their arrival, Jos Engelen, the Chief Scientific Officer, gave the IBM group an introduction to CERN. Bednorz came to CERN only recently for the Open Days to give a seminar, but unfortunately did not have time to visit the experiments, so this trip was organised instead.

Along with Alex Müller, Bednorz was awarded the Noble Prize for his discovery of superconductivity for the so-called high temperature superconductors, essentially copper-oxide-based compounds showing superconductivity at temperatures much higher than had previously been thought possible. The LHC magnets are built with low-temperature superconductors but many current leads that supply power to the LHC cryostats are made with this kind of high-temperature superconductor. Without Bednorz’s discovery the LHC would need significantly more power.

The visit had a special focus on the LHC’s famous magnets, with trips to the LHC tunnel to see his invention in place in the high temperature superconducting current leads, and to the test hall for superconducting magnets. They also visited ATLAS, with its huge magnet system. The tour ended in the silicon facility where delicate operations such as the assembly of silicon-based ALICE, CMS and LHCb detector elements and electronics takes place.

Herman Ten Kate, from the ATLAS collaboration, accompanied Bednorz throughout his trip and was surprised by his and his colleagues’ level of interest in the work at CERN. "They were all very interested and, quite unusually, they overwhelmed us with questions the entire day long. Apparently they had a great time and learnt a lot. "

Before they left, the IBM group invited interested scientists from CERN to take a return trip to their laboratory in Zurich – a chance they will surely not want to miss!