Centenary of the discovery of superconductivity

To mark the centenary of the discovery of the phenomenon of superconductivity, MANEP and the University of Geneva are organising open days at the PhysiScope between 8 and 15 April 2011. On 13 April CERN will make a contribution to the series of events with a lecture on superconductivity followed by a demonstration of the phenomenon at the Globe


Historic graph showing the superconducting transition of mercury, measured in Leiden in 1911 by H. Kamerlingh Onnes.

On 8 April 2011 it will be a hundred years since the discovery of superconductivity by the Dutch physicist Kamerlingh Onnes. To mark the occasion, the University of Geneva and MANEP are organising a week-long interactive workshop at the PhysiScope. “The purpose of this initiative is to introduce the general public to this spectacular phenomenon by giving them an opportunity to take part in entertaining experiments”, explains Adriana Aleman, Head of Communications of the University of Geneva.

As its contribution to the events, CERN will be organising a lecture in the Globe on 13 April given by Philippe Lebrun, an expert on the field of superconductivity in the DG Department, which will be followed by a re-enactment of the historic experiment. “At CERN superconductivity was first used in particle detectors at the large BEBC bubble chamber in the 1970s, followed a decade later by two LEP detectors which used superconducting magnets”, explains Philippe Lebrun. Over the same period, the phenomenon was also being applied in magnets and accelerating radio-frequency cavities in accelerators. This legacy from the first superconducting machines has now been passed down to the LHC, which could not function without this technology.”

The special characteristic of superconductivity lies in the capacity certain materials have to allow an electric current to pass through them without any resistance when they are cooled to very low temperatures. Superconducting materials also demonstrate unusual magnetic properties: for instance, if you place a sample of a superconductor above a magnet, it will float in the air, a phenomenon known as magnetic levitation.

The festivities associated with the discovery of superconductivity will continue this autumn at the Fête de la Science between 10 and 15 October 2011: special events for schools and for the general public will be organised at the Globe. The links between science and its applications will be highlighted for the general public in a series of exhibitions, projections of documentaries and a visit to SM18.


Applications of superconductivity

In addition to use in the LHC’s magnets and accelerating cavities, techniques linked to the phenomenon of superconductivity are used in the medical field. In magnetic resonance imaging (MRI), superconductivity makes it possible to produce large volumes of magnetic fields without the need to develop huge machines and provides perfect field stability. More recently, superconductivity is beginning to be used to develop more compact and efficient electrotechnical machines because it reduces energy loss during the transit of the electric current.

Other applications are being studied such as the transport of electrical energy derived from the sun’s energy over long distances from the South to the North via superconducting power lines across the Mediterranean.


by Anaïs Vernède