Helium-3 refrigerators

We offer economic access to ultra-low temperatures with our miniature helium-3 refrigerators. These remarkable devices offer access to temperatures in the range 0.30 to 0.35 K for run-times of up to 24 hours on a device that fits easily into a standard design liquid helium cryostat. The device mounts directly onto the cold plate of a helium bath cryostat requires only 4-wire connection to the outside world and the helium-3 is entirely self-contained; there is no risk of losing helium-3 in normal operation.

Device features

• Straightforward operation
• Sealed, self-contained unit. No external plumbing or valves
• Cool down to 0.35 K from 4.2 K in about 60 minutes
• Continuous run time > 24hrs at 0.35 K (4.2 K bath)
• Continuous run time > 5 days at 0.30 K (1.6 K bath)
• Units can be recycled indefinitely. Total recycling takes about 1hr
• Standard unit approximately 10cm x 5cm base, 8 cm high
• Circular 5 cm diameter horizontal work surface

Single stage helium-3 minifridge 

Recycling can be carried out indefinitely. Detectors or sample materials up to 250 g can be attached to the work surface. Larger or more massive loads can be accommodated by custom designed refrigerators.

These devices represent a reduction in the complexity of ultra-low temperature techniques for a wide range of applications. The refrigerators will fit into many standard small capacity liquid helium-4 bath cryostats.

The single stage refrigerator requires that the host cryostat helium Dewar be pumped to reach a temperature of around 1.8 K during cool-down. Our dual-stage version runs from a 4.2 K base temperature and is easier to use. 

A sophisticated large volume triple-stage helium refrigerator 

All refrigerators are leak and pressure tested to comply to BS 5500 to at least 35% over the working pressure

All QMC Instruments Ltd. products are covered by a full two year guarantee.