AdS Waves as Exact Solutions to Quadratic Gravity
  We give an exact solution of the quadratic gravity in D dimensions. The solution is a plane fronted wave metric with a cosmological constant. This metric solves not only the full quadratic gravity field equations but also the linearized ones which include the linearized equations of the recently found critical gravity. A subset of the solutions change the asymptotic structure of the anti-de Sitter space due to their logarithmic behavior. 
Ibrahim Gullu, Metin Gurses, Tahsin Cagri Sisman, Bayram Tekin
hep-th gr-qc