Slow propagation of 2 GHz acoustical waves in a suspended GaAs on insulator phononic waveguide

Abstract

Optoelectronic oscillators have dominated the scene of microwave oscillators in the last few years thanks to their great performances regarding frequency stability and phase noise. However, miniaturization of such a device is an up to date challenge. Recently, devices based on phonon-photon interaction gather a lot of interest thanks to their extreme compactness and working frequency directly in the GHz. In this frame, a still missing element to obtain long-term frequency stability performances is an on-chip delay within the feedback loop. Here, we experimentally show filtering and slow propagation of 2 GHz acoustic waves on a Gallium Arsenide membrane heterogeneously integrated on silicon wafer. By engineering the dispersion of an acoustical waveguide, we evidence a group velocity below 1000 m/s for the mode able to propagate. Thus, an integrated delay implementation is at reach for potential improvement of opto-acoustic devices such as optomechanical oscillators or wireless applications.

References in corpus (8)

• Cavity Optomechanics
• Optomechanical Crystals
• Coherent coupling between radio frequency, optical, and acoustic waves in piezo-optomechanical circuits
• Proposal for an Optomechanical Traveling Wave Phonon-Photon Translator
• Microwave-to-optics conversion using a mechanical oscillator in its quantum groundstate
• Phononic band structure engineering for high-Q gigahertz surface acoustic wave resonators on lithium niobate
• Piezoelectric transduction of a wavelength-scale mechanical waveguide
• Injection locking of optomechanical oscillators via acoustic waves

Cited by in corpus (2)

• Multimode optomechanics with a two-dimensional optomechanical crystal
• Buckling-induced quadratic nonlinearity in silicon phonon waveguide structures