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Novel in-gap spin state in Zn-doped La_1.85Sr_0.15CuO_4

H. Kimura·M. Kofu·Y. Matsumoto·K. Hirota
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Abstract

Low-energy spin excitations of La1.85Sr0.15Cu1-yZnyO4 were studied by neutron scattering. In y=0.004, the incommensurate magnetic peaks show a well defined ``spin gap'' below Tc. The magnetic signals at omega=3 meV decrease below Tc=27 K for y=0.008, also suggesting the gap opening. At lower temperatures, however, the signal increases again, implying a novel in-gap spin state. In y=0.017, the spin gap vanishes and elastic magnetic peaks appear. These results clarify that doped Zn impurities induce the novel in-gap state, which becomes larger and more static with increasing Zn.

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H. Kimura, M. Kofu, Y. Matsumoto, K. Hirota. 2003-03-19. Novel in-gap spin state in Zn-doped La_1.85Sr_0.15CuO_4. https://doi.org/10.1103/physrevlett.91.067002

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