Numerical study of Wigner negativity in one-dimensional steady-state resonance fluorescence

TL;DR

This study numerically explores how a two-level atom in a one-dimensional waveguide can generate nonclassical light states with negative Wigner functions, highlighting the influence of waveguide boundaries and decoherence.

Contribution

It demonstrates that waveguide termination can produce Wigner-negative states and links state purity with Wigner negativity, advancing understanding of nonclassical light generation.

Findings

Wigner-negative states are generated with waveguide termination.

Infinite waveguides produce only positive Wigner functions.

Decoherence reduces Wigner negativity.

Abstract

In a numerical study, we investigate the steady-state generation of nonclassical states of light from a coherently driven two-level atom in a one-dimensional waveguide. Specifically, we look for states with a negative Wigner function, since such nonclassical states are a resource for quantum information processing applications, including quantum computing. We find that a waveguide terminated by a mirror at the position of the atom can provide Wigner-negative states, while an infinite waveguide yields strictly positive Wigner functions. Moreover, our investigation reveals a connection between the purity of a quantum state and its Wigner negativity. We also analyze the effects of decoherence on the negativity of a state.