High frequency mechanical excitation of a silicon nanostring with piezoelectric aluminum nitride layers

Abstract

A strong trend for quantum based technologies and applications follows the avenue of combining different platforms to exploit their complementary technological and functional advantages. Microand nano-mechanical devices are particularly suitable for hybrid integration due to the easiness of fabrication at multi-scales and their pervasive coupling with electrons and photons. Here, we report on a nanomechanical technological platform where a silicon chip is combined with an aluminum nitride layer. Exploiting the AlN piezoelectricity, Surface Acoustic Waves are injected in the Si layer where the material has been localy patterned and etched to form a suspended nanostring. Characterizing the nanostring vertical displacement induced by the SAW, we found an external excitation peak efficiency in excess of 500 pm/V at 1 GHz mechanical frequency. Exploiting the long term expertise in silicon photonic and electronic devices as well as the SAW robustness and versatility, our technological platform represents a strong candidate for hybrid quantum systems.

Dispersive optomechanics of supercavity modes in high-index disks

“…The achievable Q factors are not so high as in the case of free-space Fabry Perot cavities [5] or silica toroids [6] but still large enough (≈ 10 5 ) as to operate in the so-called single sideband regime that enables the observation of intriguing phenomena such as ground-state cooling [7]. Finally, this technological approach permits the on-chip integration of the OMCs with electro-mechanical devices [8], which ultimately enable bidirectional and coherent microwaveoptics transducers [9].…”