Yangian Symmetry of String Theory on AdS₃xS³xS³xS¹ with Mixed 3-form Flux

Author: Antonio Pittelli

Preprint Number: UUITP-40/17

We find the Yangian symmetry underlying the integrability of type IIB superstrings on AdS₃xS³xS³xS¹ with mixed Ramond-Ramond and Neveu-Schwarz-Neveu-Schwarz flux. The abstract commutation relations of the Yangian are formulated via RTT realisation, while its matrix realisation is in evaluation representation and depends on the quantised coefficient of the Wess-Zumino term. The construction naturally encodes a secret symmetry of the worldsheet scattering matrix whose generators map different Yangian levels to each other. We show that in the large effective string tension limit the Yangian becomes a deformation of a unitary loop algebra and derive its universal, representation independent classical r-matrix.