Heike Kamerlingh Onnes when his notebook was deciphered a century later). He reported that ""Mercury has passed into a new state, which on account of its extraordinary electrical properties may be called the superconductive state"". He published more articles about the phenomenon, initially referring to it as ""supraconductivity"" and, only later adopting the term "superconductivity". Kamerlingh Onnes received widespread recognition for his work, including the 1913 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"". Some of the instruments he devised
Frans Michel Penning Derksen in 1921 and they had four children named Lourens, Hendricus, Paul, and Nellie. In 1924, Penning was hired as an experimental physicist at the Dutch section of the Phillips research department located in the Strijp district of Eindhoven. Gilles Holst, former assistant to Heike Kamerlingh Onnes, and head of the Philips Natuurkundig Laboratorium (NatLab), tasked Penning with continuing research on gas discharge phenomena to develop new lamps. Penning investigated breakdown energy potentials of low pressure inert gas discharges. In 1926, Penning observed that electrons under direct voltage current in low-pressure mercury discharges reach high velocities due to high-frequency oscillations