pleasehelpmeno said:Hi
Can anyone surmise the advantages and disadvantages of ultra low below 1K cooling methods:
cryostat cooling (HE3) as compared to Nuclear diamagnetisation
HE3 and Nuclear Diamagnetisation are two different techniques used for ultra low cooling in scientific experiments. HE3, or Helium-3, is a rare isotope of helium that has unique properties that make it ideal for cooling materials to extremely low temperatures. Nuclear Diamagnetisation, on the other hand, involves using a strong magnetic field to cool materials. Both methods have their own advantages and disadvantages, and the choice between them depends on the specific needs of the experiment.
HE3 cooling involves using a process called adiabatic demagnetization to cool materials. This process works by exposing a material to a strong magnetic field, which aligns the magnetic moments of the atoms in the material. The material is then isolated from the magnetic field and its temperature is measured. The magnetic field is then slowly reduced, causing the atoms to become disordered and decreasing the material's temperature. This process can be repeated multiple times to reach ultra low temperatures.
Nuclear Diamagnetisation has the advantage of being able to reach lower temperatures than HE3 cooling. It also does not require the use of expensive and rare HE3 gas, making it a more cost-effective option. Additionally, Nuclear Diamagnetisation can be used with a wider range of materials, while HE3 cooling is limited to materials that can be cooled in a magnetic field.
The main limitation of HE3 cooling is the scarcity of HE3 gas. It is a rare isotope and can only be produced through nuclear reactions, making it expensive and difficult to obtain. This makes HE3 cooling less accessible to researchers and limits its use in certain experiments. Additionally, HE3 cooling is not suitable for all materials, as some may not be able to withstand the strong magnetic fields required for this method.
The choice between HE3 and Nuclear Diamagnetisation cooling depends on the specific needs of the experiment. However, Nuclear Diamagnetisation is generally more commonly used due to its lower cost and ability to reach lower temperatures. HE3 cooling is reserved for experiments that require the lowest possible temperatures or for materials that cannot be cooled using Nuclear Diamagnetisation.