1995/02/02 by Mihir Arjunwadkar, Arjunwadkar, Mihir, D. G. Kanhere +5
Chemistry · Physics and Astronomy · #Condensed Matter (cond-mat) #FOS: Physical sciences #Inorganic Fluorides and Related Compounds #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys
paper · pdf · doi:10.48550/arxiv.cond-mat/9502008
openalex publication_date 1995/02/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
One of the most debated issues related to high-Tc superconductivity is the symmetry of the Cooper pair or the gap function. In this report, we present numerical results regarding the gap function in strongly correlated electron systems using t-J and Hubbard models in one and two dimensions. To this end, we use exact diagonalization to study the ground states of 8- and 16-site clusters consisting of single or coupled layers. We calculate a reduced two-particle density matrix in momentum space which is a measure of the gap function. We then analyze the eigenvectors of this density matrix, which display the possible Cooper pair symmetries. The eigenvector corresponding to the largest eigenvalue indicates a vanishing gap on the Fermi surface (which is in favour of odd-gap pairing) although dx2-y2 symmetry is seen to be a very close contestant in many of the cases.