2018/07/25 by A. D. Chepelianskii, Masamitsu Watanabe, Kimitoshi Kono · 3 citations
Materials Science · Physics and Astronomy · #Atomic and Subatomic Physics Research #Cyclotron resonance #Electron #Electron cyclotron resonance #Electron temperature #Helium #Hydrogen Storage and Materials #Liquid helium #Microwave #Overheating (electricity) #Quantum, superfluid, helium dynamics #Thermal #cond-mat.mes-hall
paper · pdf · doi:10.1007/s10909-019-02168-9
published in Journal of Low Temperature Physics 195(3-4), 307-318 (Springer Science+Business Media) · for the Electrons and Ions in quantum fluids and solids (EIQFS2018) J. Low. Temp. Phys. special issue
arxiv created 2018/07/25 · openalex created_date 2018/08/03 · openalex publication_date 2019/03/07 · arxiv updated 2019/03/27 · openalex updated_date 2026/08/05
We address the problem of overheating of electrons trapped on the liquid helium surface by cyclotron resonance excitation. Previous experiments, suggest that electrons can be heated to temperatures up to 1000K more than three order of magnitude higher than the temperature of the helium bath in the sub-Kelvin range. In this work we attempt to discriminate between a redistribution of thermal origin and other out-of equilibrium mechanisms that would not require so high temperatures like resonant photo-galvanic effects, or negative mobilities. We argue that for a heating scenario the direction of the electron flow under cyclotron resonance can be controlled by the shape of the initial electron density profile, with a dependence that can be modeled accurately within the Poisson-Boltzmann theory framework. This provides an self consistency-check to probe if the redistribution is indeed consistent with a thermal origin. We find that while our experimental results are consistent with the Poisson-Boltzmann theoretical dependence but some deviations suggest that other physical mechanisms can also provide a measurable contribution. Analyzing our results with the heating model we find that the electron temperatures increases with electron density under the same microwave irradiation conditions. This unexpected density dependence calls for a microscopic treatment of the energy relaxation of overheated electrons.