Current Leads

One of the challenges of using superconducting magnets is the connection of the magnet to a room temperature power supply. This is accomplished via current leads. The trick is that current leads should ideally have a low heat leak, since they connect room temperature to cryogenic temperature, while at the same time they should have … Continue reading Current Leads

Transfer Lines

Transfer lines may in some real sense be thought of as the cryogenic fluid analogy of current leads. While current leads carry electrical power to where it’s required in a cryogenic system, transfer lines do the same with cryogenic fluids. Transfer lines range in complexity from very simple U-tubes containing only one fluid line to … Continue reading Transfer Lines

Zero Boiloff

Zero Boil Off cryostats are those that contain liquid cryogens but are designed to eliminate or vastly reduce the boil off of  the liquid. These cryostats combine some of the advantages of Cryogen-Free systems (e.g. ease of use and long operational lifetime) with the advantages associated with a reservoir of liquid cryogens. Such a reservoir can … Continue reading Zero Boiloff


Cryomodule is a term that is most commonly used to refer to cryostats that contain superconducting radio frequency (SRF) cavities. Such cavities are used to accelerate charged particle beams and are a major component of modern particle accelerators. Using the term cryomodule to refer to cryostats containing SRF cavities appears to stem from the original … Continue reading Cryomodule

Adiabatic Demagnetization Refrigeration

Reaching temperatures below 1K requires different techniques than the various helium gas cycles found in large scale refrigeration plants and small cryocoolers. One of these techniques is Adiabatic Demagnetization Refrigeration (ADR). This technique takes advantage of the fact that the entropy of paramagnetic materials in a magnetic field is lower than when no field is present. … Continue reading Adiabatic Demagnetization Refrigeration


A cryogen is any fluid that operates at cryogenic temperatures (below roughly 150K – 120K). Using this definition, helium gas at 40K is a cryogen. Another more restrictive definition is to use cryogen to refer specifically to liquids at cryogenic temperatures. This is generally how it is used in the term cryogen-free. Thus, a cryogen-free … Continue reading Cryogen-Free

Helium II

Helium II (He II) refers to the second liquid phase of the most abundant helium isotope (4He). Helium II is also referred to as superfluid helium. Helium II occurs once the temperature of the liquid helium drops below 2.17K. The phase transition between the first liquid phase of Helium (referred to as Helium I) and … Continue reading Helium II

GE to develop wind turbine generator based on MRI magnet technology

With the wind industry moving toward larger wind turbine platforms in the future, GE Global Research, the technology development arm of the General Electric Company, has announced it has begun work on the first phase of a 2-year, $3 million project from the US Department of Energy to develop a next generation wind turbine generator that could support large-scale wind applications in the 10-15MW range.