arXiv subjects

X. Lin

Publications and source records attributed to X. Lin.

39 records · Page 3Linked to original sources

arXiv2008

Nernst effect of the new iron-based superconductor LaO$_{1-x}$F$_{x}$FeAs

We report the first Nernst effect measurement on the new iron-based superconductor LaO$_{1-x}$F$_{x}$FeAs $(x=0.1)$. In the normal state, the Nernst signal is negative and very small. Below $T_{c}$ a large positive peak caused by vortex motion is observed. The flux flowing regime is quite large compared to conventional type-II superconductors. However, a clear deviation of the Nernst signal from normal state background and an anomalous depression of off-diagonal thermoelectric current in the normal state between $T_{c}$ and 50 K are observed. We propose that this anomaly in the normal state Nernst effect could correlate with the SDW fluctuations.

cond-mat.supr-con↗

arXiv2007

The effect of 3He impurities on the nonclassical response to oscillation of solid 4He

We have investigated the influence of impurities on the possible supersolid transition by systematically enriching isotopically-pure 4He (< 1 ppb of 3He) with 3He. The onset of nonclassical rotational inertia is broadened and shifts monotonically to higher temperature with increasing 3He concentration, suggesting that the phenomenon is correlated to the condensation of 3He atoms onto the dislocation network in solid 4He.

cond-mat.other↗

arXiv2006

Search for Superfluidity in Solid Hydrogen

A torsional oscillator study of solid para-hydrogen has been carried out down to 20 mK in search for evidence of superfluidity. This work was inspired by the observation of the supersolid phase in solid He-4. We found evidence of a possible phase transition, marked by an abrupt increase in the resonant period of oscillation and onset of extremely long relaxation times as the temperature was raised above 60 mK. The change in the period for para-hydrogen, in contrast to solid He-4, is not related to superfluidity as it fails a crucial test showing that it is not a consequence of irrotational flow. The long relaxation times observed suggest the effect is related to the motion of residual ortho-hydrogen molecules in the solid.

cond-mat.other↗