On the Bilayer Coupling in the Yttrium-Barium Family of High Temperature Superconductors

Дата и время публикации : 1995-06-20T11:58:36Z

Авторы публикации и институты :
A. J. Millis (AT&T Bell Laboratories)
H. Monien (ETH Zuerich)

Ссылка на журнал-издание: Ссылка на журнал-издание не найдена
Коментарии к cтатье: 11 pages, 3 postscript figures (uuencoded and compressed)
Первичная категория: cond-mat

Все категории : cond-mat

Краткий обзор статьи: We present and solve a model for the susceptibility of two CuO2 planes coupled by an interplane coupling J_perp and use the results to analyze a recent "cross-relaxation" NMR experiment on Y2Ba4Cu7O15. We deduce that in this material the product of J_perp and the maximum value of the in-plane susceptibility chi_max varies from approximately 0.2 at T = 200 K to 0.4 at T = 120 K and that this implies the existence of a temperature dependent in-plane spin correlation length. Using estimates of chi_max from the literature we find 5 meV < J_perp < 20 meV. We discuss the relation of the NMR results to neutron scattering results which have been claimed to imply that in YBa2Cu3O_{6+x} the two planes of a bilayer are perfectly anticorrelated. We also propose that the recently observed 41 meV excitation in YBa2Cu3O7 is an exciton pulled down below the superconducting gap by J_perp.

Category: Physics