Heike Kamerlingh Onnes

Heike Kamerlingh Onnes, was born on September 21, 1853, at Groningen, The Netherlands, and is probably most well-known for being the first to liquify helium in 1908 and for his discovery of superconductivity in 1911.

While many physicists at the time were trying to see how close they could get to reaching lower and lower temperatures by liquefying nitrogen, oxygen and hydrogen, Onnes was more interested in using cryostats. Onnes managed, using the Joule-Thomson effect, to lower the temperature to less than one degree above absolute zero, reaching 0.9 Kelvin (K).

Onnes studied under Robert Bunsen and Gustav Kirchhoff at the University of Heidelberg from 1871 to 1873. Then at the University of Groningen, Onnes obtained his masters in 1878 and a doctorate in 1879. From 1882 to 1923 he served as professor of experimental physics at the University of Leiden. In 1904, Onnes founded a very large cryogenics laboratory and invited other researchers to the location. This institution led to Onnes' high regard within the scientific community.

In 1911, Onnes conducted electrical analysis of pure metals (mercury, tin and lead) at very low temperatures. Some, such as William Thomson, believed that electrons flowing through a conductor would come to a complete halt. Others, including Onnes, felt that a conductors’ electrical resistance would steadily decrease and drop to nil. At 4.2 Kelvin the resistance was zero. Onnes stated that "mercury has passed into a new state, which on account of its extraordinary electrical properties may be called the superconductive state". Onnes published more articles about the phenomena. Initially, Onnes liked using the term "supraconductivity" for the phenomena. Then later began using the term "superconductivity".

In 1913, Onnes received the Nobel Prize in physics for (in the words of the committee) "his investigations on the properties of matter at low temperatures which led, inter alia, to the production of liquid helium".

Additional bios:

http://nobelprize.org/physics/laureates/1913/onnes-bio.html
http://en.wikipedia.org/wiki/Heike_Kamerlingh-Onnes