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Physics

Sy-Hwang Liou Publications

1992

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Giant Suppression Of Flux-Flow Resistivity In Heavy-Ion Irradiated Tl2Ba2Ca2Cu3O10 Films: Influence Of Linear Defects On Vortex Transport, R.C. Budhani, M. Suenaga, Sy_Hwang Liou Dec 1992

Giant Suppression Of Flux-Flow Resistivity In Heavy-Ion Irradiated Tl2Ba2Ca2Cu3O10 Films: Influence Of Linear Defects On Vortex Transport, R.C. Budhani, M. Suenaga, Sy_Hwang Liou

Sy-Hwang Liou Publications

A large shift of the onset of flux-flow resistivity and the irreversibility line Hirr (T) to higher temperatures is observed in Tl2Ba2Ca2Cu3O10 films containing linear defects created by Ag+21 ion irradiation. The Hirr(T), which has a characteristic ssL shape in highly anisotropic Tl and Bi based cuprates, becomes more like that of YBa2Cu3O7 in the presence of these defects. The Jc at 77 K also shows a large increase as a result of flux localization at the …


Crystalline Orientations Of Tl2Ba2Ca2Cu3OΧ Grains On Mgo, Srtio3, And Laalo3 Substrates, Sy_Hwang Liou, C.Y. Wu Jun 1992

Crystalline Orientations Of Tl2Ba2Ca2Cu3OΧ Grains On Mgo, Srtio3, And Laalo3 Substrates, Sy_Hwang Liou, C.Y. Wu

Sy-Hwang Liou Publications

Crystalline orientations of Tl2Ba2Ca2Cu3Oχ grains in magnetron sputtered films on MgO (001), SrTiO3 (001), and LaAlO3 (001) substrates were investigated by scanning electron microscopy. In contrast to the nearly single crystalline films on the lattice matched substrates SrTiO3 and LaAlO3, films on the MgO (001) substrate, being polycrystalline in nature, exhibit several preferred in-plane grain orientations. These orientations agree well with a simplified theory of near-coincidence site lattices between Tl2Ba2Ca2Cu3Oχ and MgO.


Magnetic Relaxation And Irreversibility In A Superconducting Tl2Ba2Ca2Cu3O10±X Thin Film, V.K. Chan, Sy_Hwang Liou Mar 1992

Magnetic Relaxation And Irreversibility In A Superconducting Tl2Ba2Ca2Cu3O10±X Thin Film, V.K. Chan, Sy_Hwang Liou

Sy-Hwang Liou Publications

The magnetic relaxation in a Tl2Ba2Ca2Cu3O10±x superconducting thin film has been measured at a range of temperatures (5–70 K) and field strengths (500–5000 Oe). Measurements reveal that the relaxation obeys a logarithmic time dependence in the time interval 2000 s<t<12 000 s. The relaxation rate is both temperature and field dependent. The average pinning potential U* calculated from the relationship U*=kT/[(-1/Mi)dM/d lnt] is in the range 20–70 meV, which is similar to those of Y-Ba-Cu-O and (Bi,Pb)-Sr-Ca-Cu-O. The anomalous increase of U* at higher temperature is found to be closely related to …