Fermionic T-Duality of $AdS_n \times S^n (\times S^n) \times T^m$ using IIA Supergravity

Abstract

We show that the string backgrounds AdS2 x S2 x T6 and AdSd x Sd x Sd x T{10 - 3d} (d = 2, 3) are self-dual under a series of bosonic and fermionic T-dualities. We do this using the fermionic Buscher rules derived by Berkovits and Maldacena, thus working at the level of the supergravity fields. This allows us to explicitly track the behaviour of the RR fields, from which we see that we need T-duality along some torus directions. For the AdS x S x S cases, which contain cosets of D(2,1;alpha), it is necessary to perform bosonic T-duality along some complexified Killing spinors in one of the spheres.