Abstract
The magnetic structure of the high-TC superconductors has been investigated using the high-resolution technique of decorating the sample by small ferromagnetic particles. The flux line lattice was observed in single crystals Y1Ba2Cu3Ox,Ho1Ba 2Cu3Ox' Tl2Ba2Ca1Cu2O and Bi2Sr2Ca1Cu2Ox. It was found out that the flux quantum is ΦO = hc/2e = 2.07*10-7 G*cm2 in the investigated high-Tc superconductors, as in traditional superconductors. A possibility of estimating the penetration depth from observation of single vortices in low magnetic fields is discussed. An interaction between the flux line lattice and the crystal lattice is considered. A compression of the regular triangular lattice of vortices was observed in the a - b plane in a single domain area of the orthorhombic YBa2Cu3Ox single crystal. This compression is an evidence of vortex anisotropy in this plane. The ratio of superconducting carrier effective masses in the a and b directions was estimated as μa μb = 1.4 ± 0.2. Strong pinning of Abrikosov vortices has been found by twin boundaries in Y Ba2Cu3Ox and by unidentified plane defects along (100) or (010) in Bi2Sr2Ca Cu2Ox single crystals. A triangular FLL with a long-range order has been observed in the perfect Tl2Ba2Ca Cu2Ox single crystal. The elementary pinning force exerted on the FLL from twin boundaries has been estimated for YBa2Cu3Ox single crystals. © 1990.
| Original language | English |
|---|---|
| Pages (from-to) | 1271-1284 |
| Number of pages | 13 |
| Journal | Journal of the Less-Common Metals |
| Volume | 164-165 |
| Issue number | 2 |
| Publication status | Published - 15 Oct 1990 |