Topic of research seminar: Superconductivity and Magnetism in Lanthanides-doped Bi-based Compounds
Abstract: Bismuth based superconductors are considered as high temperature oxide superconductor. BaBiO3 is a double perovskite semiconductor. It has two crystallographically independent sites of Bi in the unit cell for Bi3+ and Bi5+ (as Ba2Bi3+Bi5+O6) respectively. After doping an element at the A (Ba) or/and B (Bi) site, the band gap will be modified and superconductivity can be induced. For example, BaPb1−xBixO3−δ (0.05<x<0.30), Ba1−xKxBiO3(0.30<x<0.45), and (Na0.25K0.45) Ba3Bi4O12 are superconductors. These superconductors are usually denoted as bismuth-based superconductors. The doping of K or Na at the A site or of Pb at the B site decreases the electrons in the 6S orbit in comparison to BaBiO3, where there is one electron per 6S orbit. Therefore, these reported superconductors belong to the hole-doped system. The inverse case is the electron-doped system. The hole-doped and electron-doped cuprate-based or iron-based superconductors are well known. Bismuth-based electron-doped superconductors is a challenge.
By doping lanthanides in to bismuthates, successful synthesis of solid solutions has been carried out at ambient pressure, achieving electron doping in bismuth-based superconductors. The electron doped superconductors are promising candidates towards high temperature superconductivity. To find out more electron-doped bismuth-based superconductors, a lot of work needed to be done.. A lot of study can be carried out at fermi level to explore the mechanism of charge carrier either electron or holes. It can help to find out more superconductors, which is a great challenge which might open ways for obtaining room temperature.
Subject Field of Topic: Materials Chemistry
Name of Speaker: Dr Atria Firdous
Professorial Rank of Speaker: Assistant Professor
University Email of Speaker: [email protected]
Affiliation of Speaker: Rawalpindi Women University, Rawalpindi
Date of Seminar: (Thursday) 03 March,2022 on 1400 Hrs
Venue: CR # 202, New Building, School of Natural Sciences (SNS), National University of Sciences & Technology (NUST), Islamabad