Electronic Structure near Impurities in the Chains of YBa$_2$Cu$_3$O$_{6+x}$

Dirk K. Morr; Alexander V. Balatsky

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Electronic Structure near Impurities in the Chains of YBa$_2$Cu$_3$O$_{6+x}$

Dirk K. Morr·Alexander V. Balatsky

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Abstract

We study the electronic structure near impurities in the one-dimensional chains of YBa$_2$Cu$_3$O$_{6+x}$. Assuming chain superconductivity below $T_c$ due to a proximity coupling, we show that only a magnetic impurity induces resonance states in the local density of states. Its spatial structure reflects the particle-hole nature of chain superconductivity and thus distinguishes it from other broken symmetry phases. For a sufficiently large scattering strength, or due to interference effects arising from a second impurity, the chains undergo a quantum phase transition to a polarized state.

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Dirk K. Morr, Alexander V. Balatsky. 2001-06-28. Electronic Structure near Impurities in the Chains of YBa$_2$Cu$_3$O$_{6+x}$. https://arxiv.org/abs/cond-mat/0106616

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