ultrakylmissä

Ultrakylmissä is a Finnish term used to describe conditions, phenomena, or experiments that occur at ultracold temperatures. The term is formed from ultra- (from Latin ultra) and kylmä meaning cold, with the inessive suffix -ssä indicating a state or location: "in ultracold conditions". In scientific Finnish texts it refers to temperatures typically in the nanokelvin to microkelvin range, where quantum effects dominate.

Although the form ultrakylmissä is common in specialized discourse, it is not everyday language. It is mostly used in physics and experimental contexts, including discussions of ultracold atomic gases, Bose-Einstein condensates, and quantum degenerate gases.

Under ultrakylmissä conditions, atoms can occupy the same quantum state, leading to macroscopic quantum phenomena such as Bose-Einstein condensation, superfluidity, and high coherence lengths. Experiments typically employ laser cooling, evaporative cooling, and magnetic or optical trapping to reach these temperatures.

Experiments in ultrakylmissä require isolation from environmental heat, precise control of magnetic fields, and high-vacuum environments. Temperature is inferred from spectroscopic properties, expansion dynamics, or time-of-flight measurements.

See also ultracold atoms, Bose-Einstein condensate, quantum degenerate gas.