Supraleitung und Chemie

Superconducting nitride halides MNX (M = Ti, Zr, Hf; X = Cl, Br, I)

“…All ends up with a partial filling of the conduction bands, which are mainly Ti-3d in character. The interpretation of the band structure of K 0.5 TiNCl [8] can be made with the concept of itinerant electrons and local pairs as described by Simon [144,145]. Interestingly, the critical temperature of about 16.3 K is unaffected by the kind of alkali-metal intercalation and the degree of partial dechlorination of TiNCl.…”

Palladium site ordering and the occurrence of superconductivity in Bi2Pd3Se2−xSx

“…As both have layered crystal structures, attempts for a deeper understanding and design of superconductors based on structure-property relations [3][4][5] were encouraged. The crystal structures of cuprates like YBa 2 Cu 3 O 7À d can be easily deduced from perovskites by an ordering scheme of unoccupied O sites [4].…”

Anomalous Minimum and Scaling Behavior of Localization Length Near an Isolated Flat Band

“…Systems that exhibit flat bands have attracted considerable interest in the past decades, including optical [1,2] and photonic lattices [3][4][5][6][7], graphene [8,9], superconductors [10][11][12][13], fractional quantum Hall systems [14][15][16] and exciton-polariton condensates [17,18]. As the name suggests, a flat band is dispersionless, or in other words, its density of states (DOS) diverges at a particular energy, known as the flat band energy.…”