Collective Spin Modes in Superconducting Double Layers

Christian Helm; Franz Forsthofer; Joachim Keller

doi:10.1007/bf00768464

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arXiv · cond-mat/9606135

Collective Spin Modes in Superconducting Double Layers

Christian Helm·Franz Forsthofer·Joachim Keller

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Abstract

We investigate a double layer system with tight-binding hopping, intra-layer and inter-layer interactions, as well as a Josephson like coupling. We find that an antiferromagnetic spin polarization induces additional spin-triplet pairing (with $S_z =0$) to the singlet order parameter. This causes an undamped collective mode in the superconducting state below the particle-hole threshold, which is interpreted as a Goldstone excitation.

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Christian Helm, Franz Forsthofer, Joachim Keller. 1996-06-18. Collective Spin Modes in Superconducting Double Layers. https://doi.org/10.1007/bf00768464

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