Building blocks for boson sampling in a bulk acoustic wave resonator

Stefano Marti

PhD student at HyQu

Abstract

---

Gaussian boson sampling (GBS) is a computational scheme that can demonstrate quantum advantage under widely accepted complexity-theoretic assumptions. In GBS, squeezed bosonic states are injected into an interferometric network whose output distribution is described by classically intractable matrix functions. Notable applications of GBS include sampling molecular spectra and searching for maximum cliques in graphs. However, experimental implementations remain challenging. High-overtone bulk acoustic resonators (HBARs) host a dense spectrum of long-lived phonon modes that can be coherently controlled in a circuit quantum acoustodynamics (cQAD) device and are thus a novel platform suited for realizing GBS. Here, the building blocks of GBS are implemented with bilinear interactions between HBAR modes mediated by a transmon qubit. Together with displacements and joint measurements of the Fock basis, these complete the continuous-variable toolbox required for GBS.