3He impurities in nearly frictionless transport of solid 4He at low temperatures.
Glassy matter, when subjected to high shear rates exhibit shear thinning, that is, the viscosity diminishes with increasing shear rate. One possible outcome for the almost vanishing viscosity is nearly frictionless transport, which is possible in solid (4)He due to the presence of minute concentrations of (3)He. The glassy state of solid (4)He is also relevant to the possible onset of superfluidity in solid (4)He. By treating the solid (4)He locally as an amorphous matter and using the transition-rate dependent model together with the specific activation energy, we observe a series of sudden changes of the shearing stresses (which directly relates to the resistance) at corresponding onset temperatures of supersolid (4)He (ranging from 175 to 1200 mK) for different activation volumes of (3)He. Even at higher concentrations of (3)He than previous reported (around 1700 ppm), the supersolidity of (4)He still occurs.
Chu
Kwang-Hua W
KH
Wu C-S Centre, 3/F, 24, Lane 260, First Section, Road Muzha, Taipei, Taiwan 116, China. xjylsylugh@gmail.com