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arXiv · 1506.06958

One-point Functions in Defect CFT and Integrability

Marius de Leeuw·Charlotte Kristjansen·Konstantin Zarembo
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Abstract

We calculate planar tree level one-point functions of non-protected operators in the defect conformal field theory dual to the D3-D5 brane system with k units of the world volume flux. Working in the operator basis of Bethe eigenstates of the Heisenberg XXX_{1/2} spin chain we express the one-point functions as overlaps of these eigenstates with a matrix product state. For k=2 we obtain a closed expression of determinant form for any number of excitations, and in the case of half-filling we find a relation with the N\'eel state. In addition, we present a number of results for the limiting case of infinite k.

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Marius de Leeuw, Charlotte Kristjansen, Konstantin Zarembo. 2015-06-23. One-point Functions in Defect CFT and Integrability. https://doi.org/10.1007/jhep08(2015)098

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