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arXiv · 1903.10345

Graphene resonator as an ultrasound detector for generalized Love waves in a polymer film with two level states

Antti Laitinen·Jukka-Pekka Kaikkonen·Thanniyil S. Abhilash·Igor Todoshchenko·Juuso Manninen·Vladislav Zavyalov·Alexander Savin·Andreas Isacsson·Pertti J. Hakonen
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Abstract

We have investigated surface shear waves at 22 MHz in a 0.5-micron-thick polymer film on SiO2/Si substrate at low temperatures using suspended and non-suspended graphene as detectors. By tracking ultrasound modes detected by oscillations of a trilayer graphene membrane both in vacuum and in helium superfluid, we assign the resonances to surface shear modes, generalized Love waves, in the resist/silicon-substrate system loaded with gold. The propagation velocity of these shear modes displays a logarithmic temperature dependence below 1 K, which is characteristic for modification of the elastic properties of a disordered solid owing to a large density of two level state (TLS) systems. For the dissipation of the shear mode, we find a striking logarithmic temperature dependence, which indicates a basic relation between the speed of the surface wave propagation and the mode dissipation.

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Antti Laitinen, Jukka-Pekka Kaikkonen, Thanniyil S. Abhilash, Igor Todoshchenko, Juuso Manninen, Vladislav Zavyalov, Alexander Savin, Andreas Isacsson, Pertti J. Hakonen. 2019-03-25. Graphene resonator as an ultrasound detector for generalized Love waves in a polymer film with two level states. https://doi.org/10.1088/1361-6463/ab11a9

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