Static and dynamic structure factor in solid 4He: Absence of a glassy phase

摘要: We present results on neutron scattering in solid 4He the range of parameters where supersolidity is observed. The measurements address, among other questions, viability one possible mechanism supersolidity: via a metastable amorphous phase. have attempted to observe glassy phase by scattering. found that it impossible do this total scattering, as would be common classical solid, due an extremely large inelastic diffuse signal related anomalously strong zero-point motion helium atoms. This raises general question interpretation such signature Results from energy-resolved elastic are heavily influenced multiple neutrons which may major contribution measured signal, but allow put limit concentration ?5% polycrystal with millimeter-size crystallites and ?2% single crystal. values NCRIf, expected these limits should much lower, although exact depend strongly particular model glass-related supersolidity.