A recent study led by Professor Makoto Tsubota and Specially Appointed Assistant Professor Satoshi Yui from Osaka Metropolitan University, in collaboration with researchers from Florida State University and Keio University, has shed light on the long-standing enigma surrounding the interaction between a quantized vortex and a normal-fluid in superfluid helium-4.
At cryogenic temperatures near absolute zero (-273°C), liquid helium-4 enters a superfluid state where it exhibits a unique vortex known as a quantized vortex, originating from quantum mechanical effects. Understanding how this vortex interacts with the normal-fluid coexisting within the superfluid has been a formidable challenge. Various theoretical models have been proposed, but pinpointing the correct model has remained elusive.
To tackle this puzzle, the research team conducted numerical investigations into the interaction between a quantized vortex and a normal-fluid. Through meticulous experimentation, the researchers identified the most consistent theoretical model among several contenders. Their analysis revealed that a model accounting for changes in the normal-fluid and incorporating more accurate mutual friction was the most compatible with the experimental results.
Professor Tsubota expressed his excitement, stating, “The subject of this study, the interaction between a quantized vortex and a normal-fluid, has been a great mystery since I began my research in this field 40 years ago…. Computational advances have made it possible to handle this problem, and the brilliant visualization experiment by our collaborators at Florida State University has led to a breakthrough. As is often the case in science, subsequent developments in technology have made it possible to elucidate, and this study is a good example of this.”
The groundbreaking findings of the study have been published in the prestigious journal Nature Communications, offering crucial insights into the intricate dynamics of superfluid helium and advancing our understanding of quantum mechanical phenomena.