Chiral spin-phonon bound states and spin-spin interactions with phononic lattices

TL;DR

This paper proposes a scheme to couple spins and phonons in engineered phononic lattices, revealing chiral bound states and robust spin interactions, advancing quantum phononics and information processing.

Contribution

It introduces a novel method for creating chiral spin-phonon bound states and robust spin-spin interactions in phononic dimer and trimer lattices.

Findings

Chiral spin-phonon bound states are formed in the lattices.

Phononic collective radiation depends on topology.

Chiral bound states are robust to disorder.

Abstract

Designing unconventional interactions between single phonons and spins is fascinating for its applications in quantum phononics. Here, we propose a reliable scheme for coupling spins and phonons in phononic dimer and trimer lattices, with the combination of solid-state defects and diamond phononic (optomechanical) crystals. The dimer and trimer lattices used are an array of coupled phononic cavities with spatially modulated hopping rates. We predict a series of unconventional sound-matter interaction phenomena in this hybrid quantum system. In the dimer lattice, we show the formation of chiral spin-phonon bound states and topology-dependent phononic collective radiation. While in the trimer lattice, chiral bound states still exist and the spin relaxation is sublattice-dependent. The chiral bound states existed in both types of lattices are robust to large amount of disorder, which can mediate chiral and robust spin-spin interactions. This work provides a promising platform for phonon-based quantum information processing and quantum simulation.