A cryofuge for cold-collision experiments with slow polar molecules

Xing Wu; Thomas Gantner; Manuel Koller; Martin Zeppenfeld; Sotir Chervenkov; Gerhard Rempe

doi:10.1126/science.aan3029

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arXiv · 1710.05988

A cryofuge for cold-collision experiments with slow polar molecules

Xing Wu·Thomas Gantner·Manuel Koller·Martin Zeppenfeld·Sotir Chervenkov·Gerhard Rempe

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Abstract

Ultracold molecules represent a fascinating research frontier in physics and chemistry, but it has proven challenging to prepare dense samples at low velocities. Here we present a solution to this goal by a non-conventional approach dubbed cryofuge. It employs centrifugal force to bring cryogenically cooled molecules to kinetic energies below $1\,$K$\times k_B$ in the laboratory frame, with corresponding fluxes exceeding $10^{10}$/s at velocities below $20\,$m/s. By attaining densities higher than $10^9$/cm$^3$ and interaction times longer than $25\,$ms in samples of fluoromethane as well as deuterated ammonia, we observe cold dipolar collisions between molecules and determine their collision cross sections.

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Xing Wu, Thomas Gantner, Manuel Koller, Martin Zeppenfeld, Sotir Chervenkov, Gerhard Rempe. 2017-10-16. A cryofuge for cold-collision experiments with slow polar molecules. https://doi.org/10.1126/science.aan3029

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