Optomechanical and Photothermal Interactions in Suspended Photonic   Crystal Membranes
  We present here an optomechanical system fabricated with novel stress management techniques that allow us to suspend an ultrathin defect-free silicon photonic-crystal membrane above a Silicon-on-Insulator (SOI) substrate with a gap that is tunable to below 200 nm. Our devices are able to generate strong attractive and repulsive optical forces over a large surface area with simple in- and outcoupling and feature the strongest repulsive optomechanical coupling in any geometry to date (gOM/2{\pi} ~ -65 GHz/nm). The interplay between the optomechanical and photo-thermal-mechanical dynamics is explored, and the latter is used to achieve cooling and amplification of the mechanical mode, demonstrating that our platform is well-suited for applications in low-power mass, force, and refractive index sensing as well as and optomechanical accelerometry. 
David N. Woolf, Pui-Chuen Hui, Eiji Iwase, Mughees Khan, Alejandro W.   Rodriguez, Parag Deotare, Irfan Bulu, Steven G. John...
physics.optics