A miniaturized low-vibration cryogenic cooling system enabling continuous operation via in-situ gas cylinder replacement

In low-temperature infrared detection, conventional cooling systems such as liquid nitrogen dewars are often bulky and inconvenient. Although micromachined Joule-Thomson (MJT) coolers offer a more compact alternative, the overall system remains large due to gas cylinders whose volume scales with required operational duration. This work overcomes this fundamental trade-off in open-cycle MJT systems by introducing a dual-gas-cylinder architecture. We designed and fabricated an ultra-compact gas management system (198 × 153 × 294 mm³; total volume ≈ 9 L) integrating a 0.5 L main cylinder and a 0.1 L buffer cylinder. The main cylinder was designed to be swappable during stable low-temperature operation. To test feasibility, we coupled this system with an MJT cooler featuring a relatively high mass flow rate (21 mg/s at 122 K). By performing in-situ main cylinder replacements at nearly hourly intervals, the system achieved stable cooling below 130 K for over 4.5 h after 3 replacements and over 10 h after 9 replacements, with vibration levels comparable to passive liquid nitrogen systems. The results demonstrate that cooling durations can be extended on demand via in-situ main cylinder replacements. This work presents a miniaturized low-vibration cryogenic cooling system that decouples operational duration from a fixed system volume, greatly enhancing portability and flexibility for field-deployable high-sensitivity infrared sensing.