Closed-Cycle Refrigerator Systems

Janis Research Company's closed cycle refrigerator (CCR) systems provide low temperature environments (to 10 K and below) without the need for liquid helium or nitrogen. As a result, these systems are very simple to operate and inexpensive to maintain. When combined with an automatic temperature controller, Janis closed cycle systems become powerful tools for studying the properties of materials over a wide range of temperatures. (These pages describe systems with base temperatures from 8 - 15 K; please click here for systems with base temperatures to 4 K.)

As the name implies, closed cycle systems recirculate a fixed volume of gas to provide cooling to the sample mounting stages, and no gas is added or removed during operation. Janis CCR's utilize the Gifford-McMahon thermodynamic cycle, based on the controlled compression and expansion of helium gas. A compressor is used to provide the high pressure helium gas needed for the cycle. Flexible metal gas lines deliver the compressed helium gas to the refrigerator, and return the low pressure gas to the compressor for recirculation. The refrigerator includes two cold stages, one for cooling the sample and one for cooling a radiation shield that surrounds the sample.

CCR systems are available in two general configurations, sample in vacuum (cold finger), and sample in exchange gas (top loading). Within these broad categories, models with optical, non-optical, compact and sub-compact designs are available, some with temperature range to 475/700 K. Janis also offers systems for specific applications, including Mössbauer spectroscopy, VSM, and Hall Effect measurements.

In order to deliver your system as quickly as possible, several optical CCR configurations are available for immediate delivery from stock. Our experienced staff of physicists and engineers are also available to assist in custom designing a system to meet virtually any experimental requirement. Complete systems are available including CCR, temperature controller, and vacuum pumping station. Thank you for considering a Janis CCR system; we look forward to becoming your partner in research.