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arXiv · 0704.0419

Ultrasound attenuation of superfluid $^{3}$He in aerogel

H. C. Choi·N. Masuhara·B. H. Moon·P. Bhupathi·M. W. Meisel·Y. Lee·N. Mulders·S. Higashitani·M. Miura·K. Nagai
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Abstract

We have performed longitudinal ultrasound (9.5 MHz) attenuation measurements in the B-phase of superfluid $^3$He in 98% porosity aerogel down to the zero temperature limit for a wide range of pressures at zero magnetic field. The absolute attenuation was determined by direct transmission of sound pulses. Compared to the bulk fluid, our results revealed a drastically different behavior in attenuation, which is consistent with theoretical accounts with gapless excitations and a collision drag effect.

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H. C. Choi, N. Masuhara, B. H. Moon, P. Bhupathi, M. W. Meisel, Y. Lee, N. Mulders, S. Higashitani, M. Miura, K. Nagai. 2007-04-03. Ultrasound attenuation of superfluid $^{3}$He in aerogel. https://doi.org/10.1103/physrevlett.98.225301

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