"Hidden Itinerant-Spin Phase in Heavily Overdoped La2-xSrxCuO4Superconductors Revealed by Dilute Fe Doping: A Combined Neutron Scattering and Angle-Resolved Photoemission Study "

Rui-Hua He: M. Fujita, M. Enoki, M. Hashimoto, S. Iikubo, S.-K. Mo, Hong Yao, T. Adachi, Y. Koike, Z. Hussain, Z.-X. Shen, and K. Yamada; Phys. Rev. Lett. , 09/14/11.

Additional Authors: M. Fujita, M. Enoki, M. Hashimoto, S. Iikubo, S.-K. Mo, Hong Yao, T. Adachi, Y. Koike, Z. Hussain, Z.-X. Shen, and K. Yamada

Abstract:

We demonstrated experimentally a direct way to probe a hidden propensity to the formation of a spin-density wave in a nonmagnetic metal with strong Fermi surface nesting. Substituting Fe for a tiny amount of Cu (1%) induced an incommensurate magnetic order below 20 K in heavily overdoped La2-xSrxCuO4. Elastic neutron scattering suggested that this order cannot be ascribed to the localized spins on Cu or doped Fe. Angle-resolved photoemission revealed a strong Fermi surface nesting inherent in the pristine La2-xSrxCuO4 that likely drives this order. Our finding presents the first example of the long-sought “itinerant-spin extreme” of cuprates, where the spins of itinerant doped holes define the magnetic ordering ground state; it complements the current picture of cuprate spin physics that highlights the predominant role of localized spins at lower dopings.