Harnessing the interaction between light and matter is a central topic in quantum optics and emergent quantum technologies. Waveguide-QED (quantum electrodynamics) provides a recent framework in which such interactions, i.e. those between guided photons (particles of light) and elementary quantum emitters (real or artificial atoms), are controlled and engineered through the structure and geometry of the environment in which the two interact. Work under the preceding NSF award has demonstrated the implementation of a novel experimental platform for studies of waveguide-QED effects in the context of ultracold atoms. Here, the wells of an optical lattice (i.e. a crystal made of light) act as quantum emitters, while guided atomic matter waves play the role of light. As a matter-wave analogue of optical waveguide-QED, this platform offers exquisite tunability and control of the relevant parameters along with access to novel geometries, which are difficult to realize otherwise. The project will investigate the interplay of emitter energies, interactions and geometry to study fundamental questions in waveguide-QED, such as how quantum emitters interact with an engineered environment, how they interact with each other, and what novel phenomena can result from the interaction. The project will thereby offer a glimpse at the quantum simulation of exotic material systems, which can guide future technological efforts.
The project, which builds on prior NSF-supported work, is devoted to studies of matter-wave analogues of spontaneous-emission phenomena in photonic-crystal waveguides, using arrays of matter-wave quantum emitters in a state-selective optical lattice. The free tunability of both the excitation energy of the emitters and their vacuum coupling in this recently demonstrated platform enables the exploration of a wide range of novel effects across regimes both accessible and inaccessible to standard quantum optical systems. The project aims to investigate Markovian and non-Markovian emission dynamics into one- and higher-dimensional environments that feature multiple spectral gaps and singularities. Furthermore, the project seeks to characterize coherent couplings between emitters mediated by a dynamical bound state via quasiparticle transport and the formation of interacting many-body phases, and to exploit some of the unique features arising from collisional interactions.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
