"Second sound":
#quantumphysics #thermodynamics #superfluid #research #science

https://www.popularmechanics.com/science/a64093045/second-wave-superfluid-existence/

Even if my #PhD is over, I'm still closing some projects I had begun with my former research group in #Warsaw.

In this one, we've studied #Superfluid currents across three regimes (from #BCS to #UFG) in the presence of an obstacle. If currents are too high, vortices appear in the ring.

I can't yet tell if #Atomtronic circuitry will be developed or practical, but this hints that wires with "spikes" inside might make the currents more stable.

#Physics #HPC

https://link.aps.org/doi/10.1103/PhysRevResearch.7.013225

Massive black holes drag and warp the spacetime around them in extreme ways. Observing these effects firsthand is practically impossible, so physicists look for laboratory-sized analogs that behave similarly. Fluids offer one such avenue, since fluid dynamics mimics gravity if the fluid viscosity is low enough. To chase that near-zero viscosity, experimentalists turned to superfluid helium, a version of liquid helium near absolute zero that flows with virtually no viscosity. At these temperatures, vorticity in the helium shows up as quantized vortices. Normally, these tiny individual vortices repel one another, but a spinning propeller — much like the blades of a blender — draws tens of thousands of these vortices together into a giant quantum vortex.

With that much concentrated vorticity, the team saw interactions between waves and the vortex surface that directly mirrored those seen in black holes. In particular, they detail bound states and black-hole-like ringdown phenomena. Now that the apparatus is up and running, they hope to delve deeper into the mechanics of their faux-black holes. (Image credit: L. Solidoro; research credit: P. Švančara et al.; via Physics World)

https://fyfluiddynamics.com/2024/05/black-holes-in-a-blender/

Raumzeit im Labor: Physiker haben erstmals einen „Quantentornado“ aus flüssigem Helium erzeugt – einen Wirbel aus superfluider Flüssigkeit, der das Verhalten der Raumzeit nachbilden kann. #Quantentornado #Raumzeit #Physik #Superfluid
https://www.scinexx.de/news/physik/ein-quantentornado-als-raumzeit-simulator/

Wie fühlt sich ein Superfluid an? Experiment enthüllt erstmals thermo-mechanisches Verhalten von superfluidem Helium-3. #Superfluid #Helium3 #Physik #Materialzustand
https://www.scinexx.de/news/physik/wie-fuehlt-sich-ein-superfluid-an/

https://www.nature.com/articles/s41586-023-06018-3

"Here, we realize a Fermi gas featuring both strong, tunable contact interactions and #photon-mediated, spatially structured long-range interactions in a transversely driven high-finesse #optical cavity. Above a critical long-range interaction strength, density #wave order is stabilized in the system, which we identify via its #superradiant light-#scattering properties."