The combination of low temperature and low vibration levels is key for ultrasensitive sensing applications such as scanning probe microscopy, large-mass quantum mechanics, and gravitational wave detection. Unfortunately, closed-cycle cryostats using pulse tube or GM coolers introduce strong low-frequency vibrations starting at 1 Hz. Mass-spring systems allow passive isolation, but for low-frequency applications the required spring constants and masses become impractical. Blade-based geometric anti-spring systems are compact isolators that operate from sub-Hz frequencies, but have not been demonstrated at cryogenic temperatures. Here, we characterize a geometric anti-spring system tuned to operate at cryogenic temperatures. Our cryogenic filter uses radially arranged titanium blade springs whose effective spring constant can be tuned in-situ using a magnetic actuator. Our system achieves a vertical resonance frequency of 185 mHz at 7K, which allows reduction of vibrations at the problematic 1 Hz cooler frequency by an order of magnitude.
@article{arxiv.2509.09010,
title = {Cryogenic geometric anti-spring vibration isolation system},
author = {L. Feenstra and S. Domínguez-Calderón and K. van Oosten and H. S. M. Bohemen and T. Benschop and M. Brinkman and M. Li and E. Hennes and R. Cornelissen and B. J. Hensen and A. Bertolini and M. P. Allan},
journal= {arXiv preprint arXiv:2509.09010},
year = {2025}
}