Torsional oscillator and synchrotron x-ray experiments on solid 4He in aerogel

Abstract

X-ray diffraction experiments show that solid 4He grown in aerogel is highly polycrystalline, with a hcp crystal structure (as in bulk) and a crystallite size of approximately 100 nm. In contrast to the expectation that the highly disordered solid will have a large supersolid fraction, torsional oscillator measurements show a behavior that is strikingly similar to high purity crystals grown from the superfluid phase. The low temperature supersolid fraction is only ~3x10-4 and the onset temperature is ~ 100 mK.

References in corpus (10)

• Low Temperature Shear Modulus Changes in Solid 4-He and Connection to Supersolidity
• Luttinger Liquid in the Core of Screw Dislocation in Helium-4
• Disorder and the Supersolid State of Solid ${}^4$He
• Oscillation Frequency Dependence of Non-Classical Rotation Inertia of Solid ${}^4$He
• Observation of non-classical rotational inertia in bulk solid 4He
• Annealing Effect for Supersolid Fraction in ${}^4$He
• Nonclassical Rotational Inertia in Single Crystal Helium
• The effect of 3He impurities on the nonclassical response to oscillation of solid 4He
• Thermal History of Solid 4He Under Oscillation
• Quenched Dislocation Enhanced Supersolid Ordering

Cited by in corpus (1)

• Ultrasound study of the solid-liquid transition and solid-liquid interface of ${}^4$He in aerogels