Heike Kamerlingh-Onnes Biography

Heike Kamerlingh-Onnes

(Groningen, the Netherlands, 1853-Leiden, id., 1926) Dutch physicist, discoverer of the phenomenon of superconductivity.From 1871 to 1873 he studied at the University of Heidelberg, where he was a student of the German physicists Robert Bunsen and Gustav Kirchhoff, and received his doctorate from the University of Groningen (1879).From 1878 to 1882 he was a professor at the Polytechnic School of Delft, a position he left that same year to become professor of physics at the University of Leiden until he retired in 1923.

Influenced by the work of his compatriot Johannes van der Waals, he deduced one of the equations of state applicable to gases, which bears his name.Likewise, he studied the thermodynamic properties of gases and liquids on a wide scale of pressures and temperatures.In 1894 he founded the Leiden Cryogenic Laboratory, which today bears his name.In 1908 he succeeded in liquefying helium for the first time at a low temperature.The attempt to solidify helium did not prosper until 1926, when WH Keesom, one of his disciples, managed to carry out the experiment.

Heike Kamerlingh-Onnes then turned his attention to the study of the properties of others materials at very low temperatures.The first property he investigated was the electrical resistance of metals, that is, the tendency of a substance to prevent the flow of an electric current through it.Scientists have long known that electrical resistance tends to decrease with decreasing temperature.Therefore, they assumed that the resistance would disappear completely with a temperature of absolute zero.

What Kamerlingh-Onnes discovered, however, was the almost total absence of resistance to the passage of electricity of certain substances at temperatures above absolute zero, a phenomenon known as superconductivity.In 1911 he found that the electrical resistance of mercury disappears when it cools to about 4 ° K, making it possible to return the material to its normal state by circulating a very intense electric current through it or by applying a strong magnetic field to it.

Besides arousing great theoretical interest, superconductivity has had important applications since then; For example, superconductors are used to make magnets that are used in particle accelerators (devices used, among other things, to study subatomic particles, such as electrons and protons) and in magnetic resonance spectroscopy systems (means of diagnosis used in hospitals).

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