Quantum chemical formulation of high-T-C superconductivity

• A detailed understanding of superconductivity in the cuprates is formulated. A cluster model is defined and evaluated by means of the regularized complete active space self-consistent field method. Signatures of local pair-breaking excitations in a low-dispersive oxygen metal band, attenuated by the nearby buffer ions, and nonadiabatically spin-coupled to a disjoint antiferromagnetic band are quantified and proposed to be consistent with the spin−flip signature of high-TC superconductivity in YBa2Cu3O6+x. Critical properties of the scenario are (i) hole-clustering instabilities producing local angular (D-wave) and radial (S-wave) Cooper instabilities and (ii) nonadiabaticity between local hole cluster states and antiferromagnetism. The cuprates are said to belong to a class of superconductors for which the macroscopic ground state is accessed by means of phase coherent hole cluster resonances. This understanding is illustrated by a real-space BCS-like deduction of the superconducting gap. A microscopic understanding of the order parameter symmetry emerges.

Ämnesord

NATURVETENSKAP  -- Kemi -- Teoretisk kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences -- Theoretical Chemistry (hsv//eng)

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

mechanism

quantum chemistry

superconductivity

cuprates

Publikations- och innehållstyp

art (ämneskategori)

ref (ämneskategori)