Waveguide QED: Quantum Optics of Multiple Two-Level-Systems Strongly Coupled to 1D Bosons

Duke University, Durham NC

Investigators

Abstract

Strong interaction between light and matter leads both to novel physical phenomena and to new quantum information processing capabilities. The main systems showing such strong interactions to date are difficult to scale and connect together. In this work, a new, open, scalable system with strong interactions is studied theoretically: a one-dimensional waveguide interacting with one or several quantum systems. The quantum systems cause the photons in the waveguide to become entangled and correlated, generating a new kind of multi-photon bound state. The many effects of these bound states are being investigated, such as the associated photon blockade. Their use for quantum communication, and in particular for the cryptography task known as quantum key distribution, are being evaluated. This project substantially impacts two broader fields. First, nanoscale photonic devices often involve such waveguides and quantum systems as building blocks. The new physical effects studied here are leading to a better understanding of such elements and may lead to qualitatively new devices. Second, the emerging paradigm of "quantum networks" involves elements that look exactly like the waveguide systems proposed here. Training a junior researcher is a key impact of this project: a graduate student is involved in all aspects and so is thoroughly trained in many-body and quantum optics theory as well as potential nano-photonics and quantum information applications. Finally, the co-PIs are involved in outreach in the local schools.