The rotating CryoLEM (Cryogenic Lagrangian Exploration Module), spin-up, spin-down*

The seminal work of Packard’s group in the 80s [1] showed us pictures of quantum vortices in HeII. Twelve years ago, G. Bewley’s PhD work[2], convinced the community that frozen gas micron-sized particles are a good tool to study the dynamics of these angstrom-sized vortex lines. Since then, Lagrangian Particle Tracking has proven to be an insightful tool to study quantum turbulence[3]. Building on these progresses, we have developed a cryostat with 8 optical accesses allowing performing all possible visualization techniques (from 2D-PIV to 3D-LPT). Its temperature can be adjusted between 4.2 and 1.12K, and its uniqueness relies on the fact that it can spin (in order to polarize the vorticity field) up to 2Hz. We will present this unique infrastructure (including particle generation) and report on our first results focusing on the transient and steady states reached during and after spin-up and spin-down of the cryostat.

[1]E. J. Yarmchuk , et al., Phys. Rev. Lett. 43, 214 (1979)
[2]G. P. Bewley, et al., Nature  441, 588 (2006)
[3]W. Guo, et al., Proc. Natl. Acad. Sci. USA 111, 4653 (2014)