Multi-spin string solutions in AdS black hole and confining backgrounds Original Research Article

We study semi-classical multi-spin strings in the non-supersymmetric backgrounds of AdS black hole and Wittenʹs confining model. We consider constant radius strings with rotations along the isometries of the backgrounds. In the AdS black hole, solutions exist only if there is a non-zero spin in the black hole part. In contrast with the AdS background, we find solutions which although have no rotation in the S5 part, have a regular λ expansion in the expression for large energy. In the near-extremal D3 and D4 backgrounds, we find that strings have to be located on the confining wall. We also discuss the stability of solutions by considering the fluctuation Lagrangians.