Probing the Upper Limit of Nonclassical Rotational Inertia

Abstract

We study the effect of confinement on solid 4-He's nonclassical rotational inertia (NCRI) in a torsional oscillator by constraining it to narrow annular cells of various widths. The NCRI exhibits a broad maximum value of 20% for annuli of approximately 100 micrometer width. Samples constrained to porous media or to larger geometries both have smaller NCRI, mostly below about 1%. In addition, we extend Kim and Chan's blocked annulus experiment to solid samples with large supersolid fractions. Blocking the annulus suppresses the nonclassical decoupling from 17.1% below the limit of our detection of 0.8%. This result demonstrates the nonlocal nature of the supersolid phenomena. At 20 mK, NCRI depends on velocity history showing a closed hysteresis loop in different thin annular cells.

5 pages, 4 figures

References in corpus (12)

• Low Temperature Shear Modulus Changes in Solid 4-He and Connection to Supersolidity
• Luttinger Liquid in the Core of Screw Dislocation in Helium-4
• Superglass Phase of Helium-four
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• Oscillation Frequency Dependence of Non-Classical Rotation Inertia of Solid ${}^4$He
• Superfluidity of Grain Boundaries in Solid Helium-4
• What makes a crystal supersolid ?
• Observation of non-classical rotational inertia in bulk solid 4He
• Two New Vortex Liquids
• Nonclassical Rotational Inertia in Single Crystal Helium
• Entropy of solid He4: the possible role of a dislocation glass
• Thermal History of Solid 4He Under Oscillation

Cited by in corpus (18)

• Evidence for a Superglass State in Solid 4He
• Non-linear Elastic Response in Solid Helium: critical velocity or strain
• Interplay of Rotational, Relaxational, and Shear Dynamics in Solid 4He
• Absence of Pressure-Driven Supersolid Flow at Low Frequency
• Supersolid behavior in confined geometry
• Momentum deficit in quantum glasses
• Torsional oscillators and the entropy dilemma of putative supersolid He-4
• Non-Classical Response from Quench-Cooled Solid Helium Confined in Porous Gold
• Excitations of amorphous solid helium
• Tunnelling defect nanoclusters in hcp 4He crystals: alternative to supersolidity
• Generation Efficiencies for Propagating Modes in a Supersolid
• Andreev-Lifshitz Hydrodynamics Applied to an Ordinary Solid under Pressure
• Andreev-Lifshitz Supersolid Hydrodynamics Including the Diffusive Mode
• Simultaneous investigation of shear modulus and torsional resonance of solid 4He
• Influence of Ortho-H2 Clusters on the Mechanical Properties of Solid Para-H2
• Saga of Superfluid Solids
• Quantized vortex state in hcp solid 4He
• Shear Modulus of an Elastic Solid under External Pressure as a function of Temperature: The case of Helium