# Piezoelectric transduction of a wavelength-scale mechanical waveguide

## TL;DR

This paper demonstrates a thin-film lithium niobate piezoelectric transducer converting 1.7 GHz microwaves into mechanical waves in a 1 micron waveguide, with potential applications in phononic circuits and quantum conversion.

## Contribution

It introduces a novel design method for wavelength-scale piezoelectric transducers applicable to phononic and optomechanical quantum devices.

## Key findings

- Achieved -12 dB microwave-to-mechanical conversion efficiency.
- Demonstrated single-mode mechanical waveguiding at 1.7 GHz.
- Material loss limits current efficiency.

## Abstract

We present a piezoelectric transducer in thin-film lithium niobate that converts a 1.7 GHz microwave signal to a mechanical wave in a single mode of a 1 micron-wide waveguide. We measure a -12 dB conversion efficiency that is limited by material loss. The design method we employ is widely applicable to the transduction of wavelength-scale structures used in emerging phononic circuits like those at the heart of many optomechanical microwave-to-optical quantum converters.