QFS2016 Book of Abstracts

Abstracts

O2.3 WAVES ON QUANTUM SURFACES Todoshchenko Igor, Savin Alexander, Haataja Miika, Hakonen Pertti Aalto University, Department of Applied Low Temperature Laboratory, 00076 AALTO, Finland At an interface between two media, the 3D symmetry is broken which allows for the existence of exotic particles like Majorana fermions or anyons. A natural way to explore these surface excitations is to study surface resonances. In addition to usual capillary waves, helium at low temperatures supports phase waves, like waves of crystallization. By using a double resonance technique we have obtained the first evidence of the crystallization waves in 3 He at temperatures well below 0.5 mK. We also discuss the possibility of phase waves at the interface between two different superfluid phases of 3 He. This wave does not have usual material mass, and its inertia is due to spin supercurrents. Technion- Israel Inst. Of Technology, Department of Physics, Haifa 32000, Israel Crystallites of solid He can move in relation to each other inside the solid. We detected such motion directly, using an in-situ acoustic sensor [1]. An interesting question is what physical mechanism would enable such motion. One possibility is a fluid monolayer at the interface, acting as lubricant. Another possibility is slip of crystal grains induced by gliding dislocations. To answer this question, we constructed a new sensor made of 1micron thick conducting wire loop embedded in the solid. Magnetic flux is applied through the loop. Motion of the wire induced by moving solid will produce a current which will be detected by a SQUID amplifier. The S/N of this apparatus should be 100 times higher than before[1]. We hope to detect the motion of the solid in real time. 1. E. Livne, et al., J. Low Temp. Phys. 180,185 (2015). Physics, O2.4 Atomic force microscopy of solid He Ori Scaly, Almog Danzig, and Emil Polturak,

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