ORBITAL MAGNETISM OF SINGLET LARGE BIPOLARONS

Despite having no spin magnetism, a singlet large bipolaron in an anisotropic environment has a large anisotropic Van Vleck orbital paramagnetism. With the dislike large-bipolaron morphology envisioned for layered structures, the induced moment is aligned within the planes. The paramagnetic susceptibility and magnetic excitations of large bipolarons are suppressed in the condensate of interacting large bipolarons. Thus, carrier-related shifts of NMR frequencies and spin-lattice relaxation rates progressively fall as the temperature is lowered below T(c).