Reconfigurable quantum phononic circuits via piezo-acoustomechanical interactions

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.

Splitting phonons: Building a platform for linear mechanical quantum computing

“…It is unlikely that this acoustic approach to linear quantum computing will compete with optical approaches, in which recent implementations have somewhat smaller size elements operating at much higher speeds (31,32). However, the straightforward integration of phononic circuits with superconducting qubits might provide important opportunities for hybrid computing systems and will further support the development of phononic communication networks (33)(34)(35)(36)(37)(38), possibly integrating computational capabilities. 925 GHz, we vary the relative frequency of Q 2 (horizontal axis) with zero relative delay t while monitoring the joint excitation probability P ee after phonon capture (vertical axis).…”

Tailoring Structure‐Borne Sound through Bandgap Engineering in Phononic Crystals and Metamaterials: A Comprehensive Review

“…Thanks to the progress made in the field of nanofabrication, the field of optomechanics has seen a significant development in the last decade with significant discoveries and experimental achievements that have closed the gap between the quantum‐mechanical and classical‐wave worlds toward building advanced systems that elegantly unite photons and phonons. [ 151 ] This includes the realization of nonclassical correlations between single photons and phonons, [ 472 ] optomechanical entanglement, [ 246 ] quantum transduction, [ 473 ] optomechanical quantum teleportation, [ 474 ] reconfigurable quantum phononic circuits, [ 475 ] among others, which could facilitate the development of future quantum based devices for quantum communication, quantum memories, and quantum transducers. However, most of these recent quantum optomechanical demonstrations were performed in cryogenic environments in order to reduce thermal noise.…”

On-chip distribution of quantum information using traveling phonons

“…The ability to excite, guide, and detect traveling phonons is the basic toolbox for phonon manipulation on-chip, enabling a completely new field using traveling mechanical modes in the quantum regime. Together with a phononic phase modulator ( 43 ) and beam splitter, this work will lead to full coherent control of guided phonons and paves the way to advanced quantum acoustic experiments. Moreover, our measurements highlight the potential of phonons as ideal candidates for realizing quantum networks and repeaters, as well as for on-chip distribution of quantum information in hybrid quantum devices, for example, for interfacing microwave superconducting circuits with spin quantum memories ( 24 ) or to couple on-chip qubits using electron-phonon interaction in solids ( 22 ).…”