Bi-directional conversion between microwave and optical frequencies in a piezoelectric optomechanical device

Abstract

We describe the principles of design, fabrication, and operation of a piezoelectric optomechanical crystal with which we demonstrate bi-directional conversion of energy between microwave and optical frequencies. The optomechanical crystal has an optical mode at 1523 nm co-located with a mechanical breathing mode at 3.8 GHz, with a measured optomechanical coupling strength g om /2p of 115 kHz. The breathing mode is driven and detected by curved interdigitated transducers that couple to a Lamb mode in suspended membranes on either end of the optomechanical crystal, allowing the external piezoelectric modulation of the optical signal as well as the converse, the detection of microwave electrical signals generated by a modulated optical signal. We compare measurements to theory where appropriate.

Quantum Transduction with Adaptive Control

“…There have been significant advances toward quantum state transfer between different bosonic systems, such as conversion between microwave and mechanical/spin-wave modes [3][4][5], between optical and mechanical/spin-wave modes [6][7][8][9], and etc. Motivated by the hybrid quantum networks with optical quantum communication and microwave quantum information processing, recently there are experimental demonstrations of coherent conversion between microwave and optical signals with decent conversion efficiencies [10][11][12], but the signal attenuation and added noise still prevent us from achieving quantum transduction between microwave and optical modes.Most investigations of quantum transduction are based on the direct quantum transduction (DQT) protocol. As illustrated in Fig.…”

Coupling a Superconducting Quantum Circuit to a Phononic Crystal Defect Cavity

“…The cooperativity C ∼ 4 is already sufficient for efficient conversion of microwave photons to highly localized microwave phonons, which can in turn be upconverted efficiently to optical photons [17]-a promising route for microwave-to-optical conversion [12,14,31,32]. We note that our approach of direct coupling to a phononic Since the anharmonicity χ is negative, the resonator redshifts as its occupation n r increases; here, we plot the absolute value of the shift for clarity.…”

“…[32], where interdigitated transducers generate Lamb waves that are then focused into the nanobeam from both ends. In our scheme, only one mechanical mode, the localized mode, plays a role in the coupling.…”

Coherent Conversion Between Microwave and Optical Photons—An Overview of Physical Implementations

“…This relatively high frequency allows suppression of thermal phonons at dilution fridge temperatures, and allows resonant driving by a microwave field. An internal efficiency of (1.6 ± 0.8) × 10 −5 and an external efficiency of was demonstrated by Vainsencher et al . in AlN nanobeams.…”

“…Finally, we note that optomechanical approaches are in principle bidirectional because of the symmetry between the optical and microwave cavity fields in the Hamiltonian. In several cases, optical‐to‐microwave conversion was demonstrated.…”