Eremin M.; Eremina R.; Gafurov M.; Ivan'shin V.; Kurkin I.; Kurzin S.; Keller H.; Gutmann M.
(2000)
Systematic measurements are made of ESR spectra with g ≈ 4.2 in YBa2Cu3O6+y compounds with various doping indices y. Temperature dependences of the spectrum intensity show that the ground states of the centers are singlet ...