J. Phys. I France
Volume 3, Numéro 2, February 1993
Page(s) 585 - 589
DOI: 10.1051/jp1:1993125
J. Phys. I France 3 (1993) 585-589

Flux-quantization in one-dimensional copper-oxide models

C. M. Varma and A. Sudbø

AT&T Bell Laboratories, Murray Hill, New Jersey 07974, U.S.A.

(Received 19 October 1992, accepted 26 October 1992)

A calculation of the ground state energy $E_{\rm {0}}(\Phi)$ as a function of flux $\rm {\Phi}$ in a one-dimensional `copper-oxide model' on rings of finite circumference L, including on-site interactions, and a nearest neighbor interaction V, is presented. For V of the order of the charge-transfer gap or larger, the model extrapolated to large L exhibits flux-quantization with charge 2e. The extrapolated superfluid stiffness appears, however, finite only for not too large V. These results suggest a superconductive state at V of order the charge-transfer gap of the model, but a paired and phase-separated state at larger V.

05.30 - 74.70V - 71.30

© Les Editions de Physique 1993