Condensed Matter Physics, 2016, vol. 19, No. 4, 43702
Nature of extrinsic and intrinsic self-trapping of charge carriers in underdoped cuprate high-Tc superconductors
(Department of Physics, National University of Uzbekistan, 100174 Tashkent, Uzbekistan)
Nature of extrinsic and intrinsic self-trapping (ST) of charge carriers in cuprates have been studied theoretically. The binding energies and radii of the extrinsic and intrinsic large polarons and bipolarons in cuprates are calculated variationally using the continuum model and adiabatic approximation. We have shown that the extrinsic and intrinsic three-dimensional (3D) large bipolarons exist in underdoped cuprates at η=ε∞/ε0<0.127 and η<0.138, respectively [where ε∞ (ε0) is the optic (static) dielectric constant].
polaron, bipolaron, self-trapping, high-Tc superconductors