Bhat, S. V. ; Rastogi, A. ; Kumar, N. ; Nagarajan, R. ; Rao, C. N. R. (1994) Paramagnetic Meissner effect in YBa2Cu3O7-δ: a non-resonant microwave absorption study Physica C: Superconductivity, 219 (1-2). pp. 87-92. ISSN 0921-4534
Full text not available from this repository.
Official URL: http://www.sciencedirect.com/science/article/pii/0...
Related URL: http://dx.doi.org/10.1016/0921-4534(94)90018-3
Abstract
The low-field dependence of non resonant microwave absorption (MWA) in polycrystalline samples of YBa2Cu3O7-δ with 0.1≤δ≤0.5 has been measured at T < Tc along with simultaneous monitoring of paramagnetic impurities in the chain copper (Cu-I) sites by EPR spectroscopy. MWA exhibits a cross-over from the normal zero-field minimum to an anomalous zero-field maximum accompanied by the gradual appearance and growth of the EPR signal as δ is changed from 0.1 to 0.5. It is to be noted that in the δ = 0.3-0.4 composition range, oxygen vacancies are disordered giving rise to magnetic moments due to isolated Cu2+ impurity ions. This correlation of the anomalous MWA with isolated paramagnetic Cu2+ impurities is consistent with the presence of π junctions, earlier implicated in the paramagnetic Meissner effect (PME), which in turn is related to the anomalous MWA.
Item Type: | Article |
---|---|
Source: | Copyright of this article belongs to Elsevier Science. |
ID Code: | 85126 |
Deposited On: | 29 Feb 2012 13:42 |
Last Modified: | 13 Jul 2012 11:59 |
Repository Staff Only: item control page