TY - JOUR

T1 - Closed-cycle, low-vibration 4 K cryostat for ion traps and other applications

AU - Micke, Peter

AU - Stark, Julian

AU - King, Steven A.

AU - Leopold, Tobias

AU - Pfeifer, Thomas

AU - Schmöger, Lisa

AU - Schwarz, Maria

AU - Spieß, L. J.

AU - Schmidt, Piet Oliver

AU - Crespo López-Urrutia, José R.

N1 - Funding information: We gratefully acknowledge the MPIK engineering design office headed by Frank Müller, the mechanical workshops of MPIK under the direction of Thorsten Spranz, and of PTB headed by Frank Löffler for their expertise and fabrication of numerous intricate parts. We thank the MPIK mechanical apprenticeship workshop, led by Stefan Flicker, where a major number of parts were made and a significant amount of development work took place. We thank, in particular, Florian Säubert for devising sophisticated procedures for the manufacturing of complex parts. Additionally, we appreciated the help by Stephan Metschke, Christian Kaiser, and Alexander Ruhz. We thank Julian Glässel, Michael Drewsen, Timko Dubielzig, and Matthias Brandl for helpful discussions. Financial support was provided by the Max-Planck-Gesellschaft and the Physikalisch-Technische Bundesanstalt. S.A.K. acknowledges support by the Alexander von Humboldt Foundation. We acknowledge support from the Deutsche Forschungsgemeinschaft through Grant No. SCHM2678/5-1 and the Collaborative Research Centre “SFB 1225 (ISOQUANT).”

PY - 2019/6

Y1 - 2019/6

N2 - In vacuo cryogenic environments are ideal for applications requiring both low temperatures and extremely low particle densities. This enables reaching long storage and coherence times, for example, in ion traps, essential requirements for experiments with highly charged ions, quantum computation, and optical clocks. We have developed a novel cryostat continuously refrigerated with a pulse-tube cryocooler and providing the lowest vibration level reported for such a closed-cycle system with 1 W cooling power for a <5 K experiment. A decoupling system suppresses vibrations from the cryocooler by three orders of magnitude down to a level of 10 nm peak amplitudes in the horizontal plane. Heat loads of about 40 W (at 45 K) and 1 W (at 4 K) are transferred from an experimental chamber, mounted on an optical table, to the cryocooler through a vacuum-insulated massive 120 kg inertial copper pendulum. The 1.4 m long pendulum allows installation of the cryocooler in a separate, acoustically isolated machine room. At the experimental chamber, we measured the residual vibrations using an interferometric setup. The positioning of the 4 K elements is reproduced to better than a few micrometer after a full thermal cycle to room temperature. Extreme high vacuum on the 10-15 mbar level is achieved. In collaboration with the Max-Planck-Institut für Kernphysik, such a setup is now in operation at the Physikalisch-Technische Bundesanstalt for a next-generation optical clock experiment using highly charged ions.

AB - In vacuo cryogenic environments are ideal for applications requiring both low temperatures and extremely low particle densities. This enables reaching long storage and coherence times, for example, in ion traps, essential requirements for experiments with highly charged ions, quantum computation, and optical clocks. We have developed a novel cryostat continuously refrigerated with a pulse-tube cryocooler and providing the lowest vibration level reported for such a closed-cycle system with 1 W cooling power for a <5 K experiment. A decoupling system suppresses vibrations from the cryocooler by three orders of magnitude down to a level of 10 nm peak amplitudes in the horizontal plane. Heat loads of about 40 W (at 45 K) and 1 W (at 4 K) are transferred from an experimental chamber, mounted on an optical table, to the cryocooler through a vacuum-insulated massive 120 kg inertial copper pendulum. The 1.4 m long pendulum allows installation of the cryocooler in a separate, acoustically isolated machine room. At the experimental chamber, we measured the residual vibrations using an interferometric setup. The positioning of the 4 K elements is reproduced to better than a few micrometer after a full thermal cycle to room temperature. Extreme high vacuum on the 10-15 mbar level is achieved. In collaboration with the Max-Planck-Institut für Kernphysik, such a setup is now in operation at the Physikalisch-Technische Bundesanstalt for a next-generation optical clock experiment using highly charged ions.

UR - http://www.scopus.com/inward/record.url?scp=85067070098&partnerID=8YFLogxK

U2 - 10.48550/arXiv.1901.03630

DO - 10.48550/arXiv.1901.03630

M3 - Article

C2 - 31254988

AN - SCOPUS:85067070098

VL - 90

JO - Review of Scientific Instruments

JF - Review of Scientific Instruments

SN - 0034-6748

IS - 6

M1 - 065104

ER -