Observation of Cu NMR in antiferromagnetic PrBa2Cu3O7: Evidence for hole-band filling

Copper nuclear magnetic resonance (NMR) has been observed at plane and chain Cu sites in PrBa2Cu3O7. The field-swept NMR signal from plane Cu sites disappears due to magnetic ordering below 280 K. In the antiferromagnetic state (T=1.4 K) quadrupole-split NMR spectra from plane-site Cu nuclei can be fit using an axial electric-field gradient (Q=17 2 MHz) and an internal field Hint=65.2 0.2 kOe directed at an angle 79° 1°to the c axis. The observation of plane-Cu magnetism is consistent with the absence of doped holes on CuO2 planes in PrBa2Cu3O7, which supports the view that hole filling is important in suppressing superconductivity in Y1-xPrxBa2Cu3O7. © 1990 The American Physical Society.