Optomechanic interactions in phoxonic cavities

Abstract

Phoxonic crystals are periodic structures exhibiting simultaneous phononic and photonic band gaps, thus allowing the confinement of both excitations in the same cavity. The phonon-photon interaction can be enhanced due to the overlap of both waves in the cavity. In this paper, we discuss some of our recent theoretical works on the strength of the optomechanic coupling, based on both photoelastic and moving interfaces mechanisms, in different (2D, slabs, strips) phoxonic crystals cavities. The cases of two-dimensional infinite and slab structures will enable us to mention the important role of the symmetry and degeneracy of the modes, as well as the role of the materials whose photoelastic constants can be wavelength dependent. Depending on the phonon-photon pair, the photoelastic and moving interface mechanisms can contribute in phase or out-of-phase. Then, the main part of the paper will be devoted to the optomechanic interaction in a corrugated nanobeam waveguide exhibiting dual phononic/photonic band gaps. Such structures can provide photonic modes with very high quality factor, high frequency phononic modes of a few GHz inside a gap and optomechanical coupling rate reaching a few MHz.

Acousto-optic interactions for terahertz waves using phoxonic quasicrystals

“…Various kinds of 1D nanobeams have been fabricated. The experimental results of optomechanic or AO coupling in nanobeams are in agreement with the theoretical ones [40][41][42]. Safavi-Naeini et al theoretically and experimentally studied the interaction of optical and acoustic waves in a 2D planar snowflake crystal [43].…”

Preface to Special Topic: Selected Articles from Phononics 2013: The Second International Conference on Phononic Crystals/Metamaterials, Phonon Transport and Optomechanics, 2-7 June 2013, Sharm El-Sheikh, Egypt

“…16 The interaction of elastic waves with optical waves, i.e., optomechanics, is another topic discussed in the article collection. The nature of this interaction, and the associated complexities pertaining to non-linear mode couplings, is studied theoretically 17 and experimentally. 18 This section concludes with a proposal of an optically tunable phononic crystal that uses photo-excitation of a chalcogenide glass to cause a shift in the elastic properties and hence the location of pass bands.…”