We have measured the spin susceptibility, χs, of the CuO2 planes in the underdoped high Tc superconductor, electron spin resonance (ESR) in single crystals and aligned powders in fields up to 15.4 T. At low temperatures and high fields, χs is enhanced slightly in the B‖c orientation with respect to the B⊥c orientation. The enhancement at 15.4T (≈0.15Hc2) at 16K (0.2Tc) is small: approximately 10% of χs(Tc), suggesting that the second critical field of superconductivity, Hc2≈100T, would not suppress the pseudogap. This work demonstrates the potential of high field ESR in single crystals for studying high Tc superconductors.
ASJC Scopus subject areas
- Physics and Astronomy(all)