Speaker
Description
The rapid advances in quantum technologies have significantly increased the demand for reliable cryogenic refrigeration systems capable of cooling quantum devices. Quantum device requires a temperature level of 10-20 mK and quiet environment, because the entanglement of the superconducting qubit may not be sustained due to thermal fluctuations and mechanical vibration. This phenomenon is referred to as decoherence, and it makes a computation error. Conventional dilution refrigerators (DR), so called wet DR, are precooled by liquid helium, but a more cost-effective and easy precooling method can be achieved by using a mechanical refrigerator. This research aims to develop a pulse-tube refrigerator (PTR) capable of providing a cooling capacity of 1.5 W at 4 K. This research primarily focuses on the design and optimization of the regenerator, a key component in achieving high thermal efficiency. Based on the regenerator design, the PTR was fabricated and experimentally tested. The experimental results demonstrated that the system successfully achieved a minimum temperature of 4 K. Although the cooling capacity fell short of the 1.5 W target, this discrepancy was primarily due to the suboptimal performance of the orifice valve and the double inlet valve, which regulate phase adjustment and flow distribution within the pulse tube. The developed PTR marks a significant step in localizing cryogenic refrigeration systems for the quantum industry. It is expected to serve as the pre-cooling stage for the dry DR, which can achieve temperatures below 10 mK. Additionally, it will complement the magnetic refrigerator (MR), designed to reach temperatures below 100 mK, both of which are under development within the same consortium. This integration is expected to drive the localization of quantum technology infrastructure forward.
