Superconductivity near 30 K without copper: the Ba0.6K0.4BiO3 perovskite

Anomalous composition dependence of the superconductivity in In-doped SnTe

“…Due to the inert pair effect, it is very unusual to have 5s or 6s states at the Fermi level (indeed, in SnTe the Sn 5s states appear about 5 eV below E F ); some well-known compounds that do, such as K doped BaBiO 3 , exhibit superconductivity. 40 It is therefore very likely that the hybrid state created by the In 5s and Te 5p orbitals play a significant role in the superconductivity. This would explain why In doped SnTe exhibits an order of magnitude higher T c than self-doped SnTe, even at the same nominal hole concentration.…”

Recent results in solid state chemistry of ionic ozonides, hyperoxides, and peroxides

“…The reaction of KO2 with LiCl, NaCl, CaCl 2 , Li 2 003 and CaC0 3 at 200 -250°C leads to the formation of the respective peroxides and O2 [24]. Also, KO2 has been used for preparation of high temperature superconductors [163].…”

Doping dependence of the electronic structure ofBa1−xKxBiOKobayashi1, Mizokawa2, Ino3 et al. 1999Phys. Rev. B162100View full textAdd to dashboardCite

“…By increasing x from 0, i. e., by hole doping into BaBiO 3 , BKBO undergoes a semiconductor-to-superconductor transition at x = x c . The transition temperature (T C ) becomes highest ∼ 30 K at x = x c [2], which is the highest among the copper-free oxides. It remains superconducting up to x ∼ 0.6, above which there is a solubility limit of K atoms [10].…”

“…The hole-doped bismuthate Ba 1−x K x BiO 3 (BKBO) has been fascinating researchers since its discovery [1,2] for its diverse physical properties such as superconductivity, metal-insulator transition and charge-density wave (CDW) formation. The crystal structure is a distorted (0 ≤ x < x c ) or cubic (x c < x) three-dimensional perovskite [3], where x c ∼ 0.38.…”