Anomalous impurity effect on magnetization in frustrated one-dimensional ferro- and ferrimagnets

[摘要] Significant decrease of spontaneous magnetization in frustrated one-dimensional ferro- and ferrimagnets due to nonmagnetic impurities is predicted. Using the density-matrix renormalization group method and the exact diagonalization method, we confirm that the total spin can vanish due to a single impurity in finite chains. Introducing the picture of magnetic domain inversion, we numerically investigate the impurity-density dependence of magnetization. In particular, we show that even with an infinitesimal density of impurities, the magnetization in the ground state is reduced by about 40% from that of the corresponding pure system. Conditions for the materials which may show this anomalous impurity effect are formulated.

[发布日期] 2007-11-01

[关键词] QUANTUM RENORMALIZATION-GROUPS;SPIN LADDER SYSTEM;TRIANGULAR LATTICE;TEMPERATURE PROPERTIES;NEUTRON-SCATTERING;GROUND-STATE;ANTIFERROMAGNETISM;SR(CU1-XZNX)(2)O-3;CU1-XZNXGEO3;PEIERLS