Cooling capabilities of adiabatic demagnetization refrigerators

The development of adiabatic demagnetization refrigerators (ADR) over the last decade has resulted in significant improvements in performance and ease of use, including continuous operation, relatively high cooling power (30-35 mu W at 100 mK), and cryogen-free operation. ADR systems are small, efficient, and require no auxiliary pumps or gas-handling systems. Consequently they are compact, convenient, low-cost options for ground-based research and instrument development. This paper presents an assessment of state-of-the-art ADRs in terms of temperature and cooling power capabilities, with emphasis on their applicability to quantum fluids and solids research.