, and Mössbauer studies of (Tl,Pb)(Ba0.2Sr0.8)2Ca2Cu3Oy superconductors

Study of materials using Mössbauer spectroscopy

“…To explain the decrease in T C and carrier concentration, they suggested that microstructural distortion and excess oxygen defects induced by Fe doping encourage localisation of the cruising carrier on CuO planes as a cause. Similar types of studies were made by Kuzmann et al 243 on T1-based superconductors on introduction of the Mo ¨ssbauer nuclei 57 Fe, 119 Sn and 151 Eu into the sample. The doped Tl-based superconductors were then characterised by measuring the critical temperatures, critical currents, microstructure and composition of the sample in superconducting and secondary phases.…”

57Fe Mössbauer study of Lu2Fe3Si5 iron silicide superconductor

“…After the discovery of cuprate high temperature superconductors (HTSC), Mössbauer spectroscopy was widely used for studies of these materials and reports of observation of some anomalies in the spectral parameters in the vicinity of the superconducting critical temperature (T c ) [3][4][5][6][7] were published. Due to the absence of commonly available Mössbauer nuclides in the cuprates, most studies were accomplished either by partial substitution of copper atoms by 57 Fe and/or 119 Sn, or by using resonant isotopes of the rare earth metals, like 151 Eu, which increases the degree of difficulty of the measurements and reduces the clarity of the results [3,5,8,9]. Recently, the discovery of iron-based superconductors, that naturally contain the common Mössbauer nuclide, 57 Fe, has triggered intense Mössbauer studies of these superconductors [10][11][12][13][14][15].…”

A Search for a Low Anisotropic Superconductor

“…Although most of the substitutions in Tl-1223 superconductors were made to improve the phase stability of these compounds but these doping can also control the carrier concentration and in turn the superconducting properties of these compounds. The rare earth cations (La, Sm, Pr, Eu) substitutions at the Ca sites in Tl-1223 superconductors have been found to lower the critical temperature and the phase stability of this compound [95][96][97][98][99]. But when one of the rare earth elements Ce was doped at Sr site the critical temperature was increased from 92K to 98K with the increased concentration of cerium.…”