Quasi Normal Modes for New Type Black Holes in New Massive Gravity

We obtain the quasi-normal mode frequencies of scalar perturbation on new type black holes in three dimensional new massive gravity. In some special cases, the exact quasi-normal mode frequencies are obtained by solving scalar field equations exactly. On some parameter regions, the highly damped quasi-normal mode frequencies are obtained in an analytic form by the so-called Stokes line method. This study on quasi-normal modes shed some light on the mysterious nature of these black holes. We also comment about AdS/CFT correspondence and the entropy/area spectrum for new type black holes.