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Neutrons for Science
in 1971 by Serge Pujol, also from TBT. Initially cryostats were ordered from French and German companies. It was quickly apparent that these commercial devices were not well adapted
to the needs. They were much too slow for the rapid cycle of experiments at the RHF and not easily usable by novices to cryogenics. An engineer, Dominique Brochier, was recruited from the CNRS/CRTBT. With Pujol, he launched the construction of cryostats at the ILL, likely to be used by non-specialists (often total beginners) and which could be mounted on one instrument or another according to needs. These were remarkably successful. Originally we had nothing prepared to recover the helium87 that spewed out of each cryostat. To reduce these costs we were obliged to install a gas recovery system, which though expensive, was quickly amortised88.
For high temperatures it was necessary to await the arrival in 1974 of Pierre Aldebert, coming from the Odeillo solar furnace, a CNRS laboratory, to prepare a thesis on refractory oxides at high temperature.
High pressures were introduced in 1971 by Christian Vettier (French deputy director, 1991-2007), who at that time worked on a thesis on samples under pressure, directed by Daniel Bloch from the laboratory of Louis Néel.
The importance of high magnetic fields was recognised later. In this field the key proponent was another student, Francis Tasset, who was preparing a thesis supervised by Jacques Schweitzer from the crystallography laboratory of the CEA-CNRS.
87 Helium is a rare gas, hence expensive.
88 2018 addition: the saving was €12.6M in 44 years of operation.
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