Experimental study on a dry dilution refrigerator driven by a high-power linear compressor

Abstract

With the development of quantum computing and other fields, dilution refrigerators are required to have greater cooling capacity. More cooling power means larger 3He flow rate and the corresponding gas circulation system. In dry dilution refrigerators, 3He needs to be pressurized by compressor for the high inlet pressure. This paper introduces a dry dilution refrigerator driven by a designed high-power two-stage linear compressor, and the reliability of the compressor is verified by experiments. 3He can be pressurized to a pressure above 200 kPa at a flow rate of nearly 1 mmol/s and be condensed successfully in the condensatiion process. The refrigerator, precooled by a pulse tube cryocooler, can obtain a minimum temperature of 19 mK and a cooling capacity of 250 μW at about 100 mK at the total flow rate of about 0.45 mmol/s. The maximum power of 3He compressor can reach 300 W and the maximum compression ratio is over 10, which can be used as the 3He driver of high-power dilution refrigerators or closed-cycle space dilution refrigerators.