Development of a cryogen-free dilution refrigerator with a cooling power of 2000 μW at around 100 mK

Employing two pulse tube cryocoolers for precooling, we constructed a single dilution refrigerator with implementation of an enhanced pumping system and four parallel dilution units within a vacuum chamber. The system achieves a base temperature of 6.6 mK and a cooling power of 2000 μW at 102.48 mK, which meets the demand for high-cooling-power dilution refrigerators in current quantum computing applications and some large-scale scientific facilities. Concurrently, we further evaluated the performance of the still and pumping system and provided experimental evidence demonstrating the impact of the amount and composition of gas mixture on refrigerator. This work establishes a benchmark for constructing equivalent-specification dilution refrigerators and offers critical reference value for developing higher-power systems.