We studied local electronic states near Zn in optimally doped ${\mathrm{YBa}}_2({\mathrm{Cu}}_{1-x}{\mathrm{Zn}}_x{)}_3{\mathrm{O}}_{7-\delta }$ and underdoped ${\mathrm{YBa}}_2({\mathrm{Cu}}_{1-x}{\mathrm{Zn}}_x{)}_4{\mathrm{O}}_8$ via satellite signals of plane-site Cu(2) nuclear quadrupole resonance (NQR) spectra. From the relative intensity of Cu NQR spectra, the satellite signals are assigned to Zn-neighbor Cu NQR lines. The Cu nuclear spin-lattice relaxation time of the satellite signal is shorter than that of the main signal, which indicates that the magnetic correlation is locally enhanced near Zn both for the underdoped and the optimally doped systems. The pure ${\mathrm{YBa}}_2{\mathrm{Cu}}_4{\mathrm{O}}_8$ is a stoichiometric, homogenous, underdoped electronic system; nevertheless, the Zn-induced inhomogeneous magnetic response in the ${\mathrm{CuO}}_2$ plane is more marked than that of the optimally doped ${\mathrm{YBa}}_2{\mathrm{Cu}}_3{\mathrm{O}}_{7-\delta }.$

• Received 9 November 2002

DOI:https://doi.org/10.1103/PhysRevB.67.064516