Shubnikov–de Haas effectAn oscillation in the conductivity of a material that occurs at low temperatures in the presence of very intense magnetic fields, the Shubnikov–de Haas effect (SdH) is a macroscopic manifestation of the inherent quantum mechanical nature of matter. It is often used to determine the effective mass of charge carriers (electrons and electron holes), allowing investigators to distinguish among majority and minority carrier populations. The effect is named after Wander Johannes de Haas and Lev Shubnikov.
CryocoolerA refrigerator designed to reach cryogenic temperatures (below ) is often called a cryocooler. The term is most often used for smaller systems, typically table-top size, with input powers less than about 20 kW. Some can have input powers as low as 2–3 W. Large systems, such as those used for cooling the superconducting magnets in particle accelerators are more often called cryogenic refrigerators. Their input powers can be as high as 1 MW.
SolidificationLa solidification est l'opération (plus ou moins réversible) au cours de laquelle un liquide passe à l'état solide. Cela peut se faire par refroidissement (cas le plus courant), par augmentation de la pression, par cristallisation, par catalyse ou bien par une combinaison de ces phénomènes. La congélation peut aussi permettre la solidification de certains fluides (l'eau par exemple). La solidification de l'eau se fait à une température de .
