Heike Kamerlingh Onnes

Heike Kamerlingh Onnes (Dutch: [ˈɦɛikə ˈkaːmərlɪŋ ˈɔnəs]; 21 September 1853 – 21 February 1926) was a Dutch experimental physicist who became the first to liquefy helium, cooling it to near 1.5 kelvin (K). For this work, he was awarded the Nobel Prize in Physics in 1913. In 1911, using liquid helium to investigate the electrical conductivity of solid mercury, Kamerlingh Onnes found that its electrical resistance vanishes at 4.2 K, i.e. superconductivity.