TY - JOUR T1 - From membrane-in-the-middle to mirror-in-the-middle with a high-reflectivity sub-wavelength grating JF - Annalen der Physik Y1 - 2015 A1 - Corey Stambaugh A1 - Haitan Xu A1 - Utku Kemiktarak A1 - J. M. Taylor A1 - John Lawall AB - We demonstrate a "membrane in the middle" optomechanical system using a silicon nitride membrane patterned as a subwavelength grating. The grating has a reflectivity of over 99.8%, effectively creating two sub-cavities, with free spectral ranges of 6 GHz, optically coupled via photon tunneling. Measurements of the transmission and reflection spectra show an avoided crossing where the two sub-cavities simultaneously come into resonance, with a frequency splitting of 54 MHz. We derive expressions for the lineshapes of the symmetric and antisymmetric modes at the avoided crossing, and infer the grating reflection, transmission, absorption, and scattering through comparison with the experimental data. VL - 527 U4 - 81 - 88 UR - http://arxiv.org/abs/1407.1709v1 CP - 1-2 J1 - ANNALEN DER PHYSIK U5 - 10.1002/andp.201400142 ER -