Dynamics of Charged Dust Near Liquid Helium Surface

Abstract

Dynamics of microscopic charged dust particles in cryogenic condition is studied experimentally. Dust particles were free falling through the liquid helium (LHe) vapor as well as through LHe. In the liquid, particles start to go up toward the surface. It was found that dust particles are charged negatively in vapor plasma, but lose the negative charge and became charged positively in the liquid, which is confirmed by the examination of the particle dynamics. Based on dust trajectories observed, the charge values for the dust particles were calculated.

Self-organization of Coulomb balls in glow DC discharge in neon at cryogenic temperature

“…For optical measurements of the dust structures and the discharge luminescence in the axial section, the cryostat was equipped with flat quartz windows (14) at the end surface of the discharge device and along the cryostat length (at an angle of 90°). Images of dust structures (15), formed by spherical melamine-formaldehyde particles with a diameter of 4.14 μm (16) were recorded in the axial section in the reflected light of a flat laser beam (17) with a microscope (18) and a CCD video camera (19). The flat laser (20) beam was formed using an optical system consisting of two cylindrical lenses (21).…”

“…Since the first experimental observation of cryogenic dusty plasma [12], an important direction in dusty plasma research is the study of its self-organization [5,6,[12][13][14][15][16][17][18][19][20]. The self-organization of dust particles in plasma with the formation of dissipative dust structures occurs as a result of the Coulomb interaction of dust particles held in glow DC discharge or high-frequency discharge plasma traps.…”

“…In plasma of various gases at cryogenic temperature, as well as at room one, the shape, size, composition, degree of order and dynamic stability of components of dust structures vary depending on the discharge parameters [6,[12][13][14][15][16][17][18][19]. The structure of the lattice sites of the dust structure may also depend on temperature.…”

Dust-Acoustic Nonlinear Waves in a Nanoparticle Fraction of Ultracold (2K) Multicomponent Dusty Plasma

“…In recent years, studies of cryogenic dusty plasma have become relevant, which is due to various fundamental and technological aspects [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ]. Notably, the study of ultra-low-temperature discharges is an independent physical problem [ 11 , 12 , 13 ].…”