Interplay of Rotational, Relaxational, and Shear Dynamics in Solid 4He

  title={Interplay of Rotational, Relaxational, and Shear Dynamics in Solid 4He},
  author={Ethan Pratt and Benjamin M. Hunt and Vikram Gadagkar and Minoru Yamashita and Matthias J. Graf and Alexander V. Balatsky and J. C. S{\'e}amus Davis},
  pages={821 - 824}
Comprehensive measurements argue against the existence of the exotic supersolid quantum state of frozen helium. Using a high-sensitivity torsional oscillator (TO) technique, we mapped the rotational and relaxational dynamics of solid helium-4 (4He) throughout the parameter range of the proposed supersolidity. We found evidence that the same microscopic excitations controlling the torsional oscillator motions are generated independently by thermal and mechanical stimulation. Moreover, a measure… 

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