High performance cryogen-free microkelvin platform

TL;DR

This paper presents a novel cryogen-free microkelvin platform utilizing nuclear demagnetization, achieving temperatures below 400 μK and enabling stable, low-noise ultralow temperature environments for advanced quantum research.

Contribution

The authors designed and optimized a nuclear demagnetization stage compatible with standard cryogen-free refrigerators, reaching sub-millikelvin temperatures with high operational stability.

Findings

Achieved temperatures as low as 395 μK.

Operates below 1 mK for 95% of the time.

Provides a low-noise environment suitable for quantum experiments.

Abstract

Improved accessibility to the microkelvin temperature regime is important for future research in quantum materials; for quantum information science; and for applications of quantum sensors. Here we report the design and performance of a microkelvin platform based on a nuclear demagnetization stage, engineered and well optimized for operation on a standard cryogen-free dilution refrigerator. PrNi5 is used as the dominant refrigerant. The platform provides a large area for mounting experiments in an ultralow temperature, low electromagnetic noise environment. The performance is characterized using current sensing noise thermometry. Temperatures as low as 395 $\mu$K have been reached, and a protocol has been established in which it is possible to operate experiments below 1 mK for 95% of the time, providing an efficient cryogen-free microkelvin environment for a wide range of science applications