Parity-Engineered Light-Matter Interaction

TL;DR

This paper demonstrates the engineering of parity in light-matter interactions using a superconducting flux qubit, enabling control over interaction types and transitions, with implications for quantum simulations.

Contribution

It introduces a method to control the parity of artificial atoms' wave functions via shaped microwave fields, advancing tunable multilevel atom design.

Findings

Observation of dipole and quadrupole selection rules.

Induction of transparency through longitudinal coupling.

Control of interaction parity in superconducting circuits.

Abstract

The concept of parity describes the inversion symmetry of a system and is of fundamental relevance in the standard model, quantum information processing, and field theory. In quantum electrodynamics, parity is conserved and large field gradients are required to engineer the parity of the light-matter interaction operator. In this work, we engineer a potassium-like artificial atom represented by a specifically designed superconducting flux qubit. We control the wave function parity of the artificial atom with an effective orbital momentum provided by a resonator. By irradiating the artificial atom with spatially shaped microwave fields, we select the interaction parity in situ. In this way, we observe dipole and quadrupole selection rules for single state transitions and induce transparency via longitudinal coupling. Our work advances the design of tunable artificial multilevel atoms to a new level, which is particularly promising with respect to quantum chemistry simulations with near-term superconducting circuits.