================ O.J. Poppema ================ - Okko Jan - geboren te Veelerveen - studie Natuurkunde te Leiden bij C.J. Gorter (*) - promotie 08 januari 1954 te Groningen - proefschrift: Nuclear orientation in solids - promotor: dr. H. Brinkman - 1 september 1960 - gewoon hoogleraar - algemene natuurkunde - vertrek 1986 - overleden 1991 = = = (*) Returning to Leiden after the war, Gorter devoted much of his energy to the transformation of the Kamerlingh Onnes Laboratory into a cryogenic lab with modern electronic and instrumental equipment. With his students D. de Klerk, M.J. Steenland, O.J. Poppema, W.J. Huiskamp, H. Postma, and A.R. Miedema he began to investigate magnetism and related subjects below 1 Kelvin by means of adiabatic demagnetization. http://www.lorentz.leidenuniv.nl/history/gorter/biography.html