Antiferromagnetic ordering and disappearance of pseudogap within the vortex core of Tl_2Ba_2CuO_{6+δ}

K. Kakuyanagi; K. Kumagai; Y. Matsuda; M. Hasegawa

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Antiferromagnetic ordering and disappearance of pseudogap within the vortex core of Tl_2Ba_2CuO_{6+δ}

K. Kakuyanagi·K. Kumagai·Y. Matsuda·M. Hasegawa

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Abstract

Spatially-resolved NMR is used to probe the magnetism in and around the vortex core of nearly optimally-doped Tl_2Ba_2CuO_{6+δ} (T_c=85K). The NMR relaxation rate T_1^{-1} at ^{205}Tl site, at which antiferromagnetic (AF) fluctuation can be monitored sensitively, provides a direct evidence that the AF spin correlation is significantly enhanced in the vortex core region. In the core region Cu spins show a local AF ordering with moment ~ 0.1μ_B parallel to the layers at T_N=20K. Above T_N the core region is in the paramagnetic state which is a reminiscence of the state above the pseudogap temperature (T*=120K), indicating that the pseudogap disappears within the core.

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K. Kakuyanagi, K. Kumagai, Y. Matsuda, M. Hasegawa. 2002-06-19. Antiferromagnetic ordering and disappearance of pseudogap within the vortex core of Tl_2Ba_2CuO_{6+δ}. https://arxiv.org/abs/cond-mat/0206362

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