Supratekutá turbulence v nanoškálovém rozlišení
| Název práce v češtině: | Supratekutá turbulence v nanoškálovém rozlišení |
|---|---|
| Název v anglickém jazyce: | Superfluid turbulence at the nanoscale |
| Klíčová slova: | supratekuté hélium|kvantová turbulence|nanofabrikace|2D systémy |
| Klíčová slova anglicky: | superfluid helium|quantum turbulence|nanofabrication|2D systems |
| Akademický rok vypsání: | 2022/2023 |
| Typ práce: | disertační práce |
| Jazyk práce: | čeština |
| Ústav: | Katedra fyziky nízkých teplot (32-KFNT) |
| Vedoucí / školitel: | Mgr. Emil Varga, Ph.D. |
| Řešitel: | skrytý - zadáno a potvrzeno stud. odd. |
| Datum přihlášení: | 13.10.2022 |
| Datum zadání: | 13.10.2022 |
| Datum potvrzení stud. oddělením: | 13.10.2022 |
| Konzultanti: | doc. RNDr. David Schmoranzer, Ph.D. |
| Zásady pro vypracování |
| Turbulent flow confined to two dimensions differs greatly from a three-dimensional turbulence due to the inversion of the turbulent cascade: the energy, rather than being cascaded to smaller and smaller scales and thus randomizing the observed flow is accumulated at large scales, which can lead to spontaneous emergence of order. This project proposes to study 2D turbulence using superfluid helium, which is a well-suited medium for on-chip nanometer-scale 2D channels.
Moreover, nanoscale mechanical systems may be used with advantage as sensitive probes of quantum turbulence with single vortex resolution. Within our international activities, the student will participate in such experiments in 3D helium superfluids and their interpretation. The student will design nanofluidic helium system based on Helmholtz resonators, which will be fabricated using modern cleanroom methods in collaboration with the CEITEC nanofabrication facility. The fabricated devices will be used to measure the nonlinear dissipation of the Helmholtz mode using a custom bridge circuit, with and without rotation of the cryostat. The experimental results will be complemented with theoretical and numerical modelling as appropriate, possibly drawing connections with natural quasi-2D systems, such as large-scale atmospheric flows. |
| Seznam odborné literatury |
| L. Skrbek et al., Fyzika Nizkých Teplot (Matfyzpress, Prague, 2011)
P. A. Davidson, Turbulence: An Introduction for Scientists and Engineers (Oxford University Press, Oxford, 2014) R. H. Kraichan and D. Montgomery, Two-dimensional turbulence, Rep. Prog. Phys. 43, 547-619 (1980) E. Varga et al., Observation of bistable turbulence in quasi-two-dimensional superflow, Phys. Rev. Lett. 125, 025301 (2020) E. Varga, J. P. Davis, Electromechanical feedback control of nanoscale superflow, New J. Phys. 23, 113041 (2021) Y. P. Sachkou et al., Coherent vortex dynamics in a strongly interacting superfluid on a silicon chip, Science 366, 1480 (2019) G. Gauthier et al., Giant vortex clusters in a two-dimensional quantum fluid, Science 364, 1264 (2019) Johnstone et al., Evolution of large-scale flow from turbulence in a two-dimensional superfluid, Science 364, 1267 (2019) |
| Předběžná náplň práce v anglickém jazyce |
| Design and fabrication of nanofluidic systems; exploration of superfluid turbulence in the 3D-to-2D crossover; study of rotating 2D turbulence and possible connections to large-scale atmospheric dynamics. |