To create a fast turn-around dilution refrigerator, we revived the form factor of our first cryogen-free dilution refrigerator. The new SD system requires no lab layout or on-site installation, and with the reduced step heat exchanger stage the required amount of helium-3 is only 12 litres, making the system an effective and affordable alternative. SD system typically provides cooling power >250 μW when operated at 100 mK with only 12 litres of helium-3.

Fully Automated Operation

Single push of a button initiated fully automated cool-down sequence from room to base temperature.

Compact and Effective

MXC Flange Diameter: 150 mm | 6″

The experimental space beneath the mixing chamber (no magnet) is 148 mm in diameter and up to 300 mm in height. The height can be easily adapted to suit your experimental requirements. The dilution unit is positioned off-center to provide maximum useful experimental space on all flanges.

Three Access Ports

2 x KF40
1 x KF25

Superior Performance

Base temperature well below 30 mK
Fast cool-down: < 12 hours to 30 mK

Temperature Controller

The Bluefors Temperature Controller enhance the user experience of our cryogenic systems. With a modern and intuitive user interface, you gain direct control and overview of the system’s temperature status.

The Bluefors Temperature Controller is fully-integrated to all dilution refrigerator systems delivered from early summer 2020.

Read more about the Temperature Controller here.

Low Total Cost of Ownership

Oil-free pumps and compressors in gas handling unit guarantee minimal maintenance requirements with service interval up to 3 years. The systems employ only high-quality components such as Pfeiffer Vacuum pumps and pressure sensors, VAT vacuum valves and bellows.

Options

Options

Optical Ports

We offer direct optical access to the sample space. The optical ports can be equipped with different window materials and are available in different sizes and configurations.

Magnetic Shielding

If required, μ-metal magnetic shielding can be fitted to some parts of the system (for example a μ-metal cylinder with one end closed inside the lower section of the vacuum can). For magnetic shielding we work together

Amuneal Manufacturing Corp.

Magnetic shielding as an option should be discussed on a case-by-case basis with our sales engineers.

4K Heater Kit

Fully automated fast warm-up option, which allows overnight warm-up for our standard SD systems.

Service Packages and Extended Warranty are available upon request

Technical

Technical Specifications

Note: Cooling power is measured on experimental flange outside MXC.

SD250	GUARANTEED	EXPECTED
Base temperature	30 mK	25 mK
Cooling power @ 100 mK	250 μW	275 μW
Cooling power @ 120 mK	360 μW	400 μW
Cool-down time to base	12 hrs	11 hrs

Performance

Performance Graphs

Above is a typical cool-down curve for a SD system measured with a calibrated resistance thermometer.

Pulse pre-cooling sequence (see spots 2 and 3) is one of the key points in reducing the cool-down time. Because we do not use exchange gas some parts of the DR unit stay ‘hot’ on cool down, which prevents condensation of the mixture. By repeatedly admitting the mixture from the tanks through the low impedance still-side of the DR and then pumping it out again, these hot spots are effectively cooled down.