Reconfigurable quantum phononic circuits via piezo-acoustomechanical interactions

Jeffrey C Taylor,Eric Chatterjee,Matt Eichenfield,Daniel Soh,William F Kindel

doi:10.1038/s41534-022-00526-2

Jeffrey C Taylor, Eric Chatterjee + Show 3 more

Open Access

https://doi.org/10.1038/s41534-022-00526-2

Copy DOI

Abstract

We show that piezoelectric strain actuation of acoustomechanical interactions can produce large phase velocity changes in an existing quantum phononic platform: aluminum nitride on suspended silicon. Using finite element analysis, we demonstrate a piezo-acoustomechanical phase shifter waveguide capable of producing ±π phase shifts for GHz frequency phonons in 10s of μm with 10s of volts applied. Then, using the phase shifter as a building block, we demonstrate several phononic integrated circuit elements useful for quantum information processing. In particular, we show how to construct programmable multi-mode interferometers for linear phononic processing and a dynamically reconfigurable phononic memory that can switch between an ultra-long-lifetime state and a state strongly coupled to its bus waveguide. From the master equation for the full open quantum system of the reconfigurable phononic memory, we show that it is possible to perform read and write operations with over 90% quantum state transfer fidelity for an exponentially decaying pulse.

Highlights

Phonons are becoming increasingly attractive for the processing and transduction of quantum information
When simultaneously localized with photons in optomechanical crystals[44,45], phonons interact strongly enough to have their quantum states teleported over optical fiber via optomechanical interactions[17,18,46,47], presenting a route to optical distribution and networking of microwave frequency quantum information[17,18,24–26,28–30,43]
Instead of employing the electro-acoustic effect of piezoelectric materials[50], we show that acoustomechanical interactions—the interactions of phonons with the materials that guide them as those materials deform and strain—provide the necessary tunability and reconfigurability to enable such phononic circuits

Summary

Introduction

Phonons are becoming increasingly attractive for the processing and transduction of quantum information. To assess the purely mechanical phase shift arising from the change in path length, we construct a finite structure in which the piezoelectric actuator extends for the central 20-periods of a waveguide that is 220 periods long.

Results

Conclusion