Phononic band structure engineering for high-Q gigahertz surface acoustic wave resonators on lithium niobate

Abstract

Phonons at gigahertz frequencies interact with electrons, photons, and atomic systems in solids, and therefore have extensive applications in signal processing, sensing, and quantum technologies. Surface acoustic wave (SAW) resonators that confine surface phonons can play a crucial role in such integrated phononic systems due to small mode size, low dissipation, and efficient electrical transduction. To date, it has been challenging to achieve high quality (Q) factor and small phonon mode size for SAW resonators at gigahertz frequencies. Here, we present a methodology to design compact high-Q SAW resonators on lithium niobate operating at gigahertz frequencies. We experimentally verify out designs and demonstrate Q factors in excess of $2\times 10^4$ at room temperature ($6\times 10^4$ at 4 Kelvin) and mode area as low as $1.87{\lambda }^2$. This is achieved by phononic band structure engineering, which provides high confinement with low mechanical loss. The frequency-Q products (fQ) of our SAW resonators are greater than $10^{13}$. These high-fQ and small mode size SAW resonators could enable applications in quantum phononics and integrated hybrid systems with phonons, photons, and solid-state qubits.

References in corpus (6)

• Phonon counting and intensity interferometry of a nanomechanical resonator
• Sub-optical wavelength acoustic wave modulation of integrated photonic resonators at microwave frequencies
• Coupling a Surface Acoustic Wave to an Electron Spin in diamond via a Dark State
• Black Phosphorus Nanoelectromechanical Resonators Vibrating at Very High Frequencies
• Surface acoustic wave devices on bulk ZnO at low temperature
• Engineering phonon leakage in nanomechanical resonators

Cited by in corpus (5)

• Coherent Acoustic Control of a Single Silicon Vacancy Spin in Diamond
• Nonreciprocal Transmission of Microwave Acoustic Waves in Nonlinear Parity-Time Symmetric Resonators
• Integrated microwave acousto-optic frequency shifter on thin-film lithium niobate
• On-chip integrated waveguide amplifiers on Erbium-doped thin film lithium niobate on insulator
• Gigahertz acousto-optic modulation and frequency shifting on etchless lithium niobate integrated platform