Heterotic AdS3/CFT2 duality with (0,4) spacetime supersymmetry

We discuss the AdS3/CFT2 duality of a heterotic three-charge model with (0,4) target space supersymmetry. The worldsheet theory for heterotic strings on the AdS3×S3/ZN×T4 near-horizon geometry was constructed by Kutasov et al. [D. Kutasov, F. Larsen, R.G. Leigh, String theory in magnetic monopole backgrounds, Nucl. Phys. B 550 (1999) 183, hep-th/9812027]. We propose that the dual conformal field theory is given by a two-dimensional (0,4) sigma model arising on the Higgs branch of an orbifolded ADHM model. As a non-trivial consistency check of the correspondence, we find that the left- and right-moving central charges of the infrared conformal field theory agree with those predicted by the worldsheet model. Moreover, using the entropy function formalism, we show that to next-to-leading order the central charge can also be obtained from an α′-corrected supergravity theory.