Phase-modulated Autler-Townes splitting in a giant-atom system within waveguide QED

TL;DR

This paper explores how phase modulation in giant atoms within waveguide QED can dynamically control photon transmission and Autler-Townes splitting, revealing size-dependent energy shifts and tunable transmission features.

Contribution

It introduces a novel method of controlling photon scattering in giant atoms through phase modulation, demonstrating size-dependent effects and tunable Autler-Townes splitting.

Findings

Photon transmission is controllable via phase modulation.

Energy shifts depend on the atomic size.

Autler-Townes splitting is significantly modulated by the giant atom size.

Abstract

The nonlocal emitter-waveguide coupling, which gives birth to the so called giant atom, represents a new paradigm in the field of quantum optics and waveguide QED. In this paper, we investigate the single-photon scattering in a one-dimensional waveguide on a two-level or three-level giant atom. Thanks to the natural interference induced by the back and forth photon transmitted/reflected between the atom-waveguide coupling points, the photon transmission can be dynamically controlled by the periodic phase modulation via adjusting the size of the giant atom. For the two-level giant-atom setup, we demonstrate the energy shift which is dependent on the atomic size. For the driven three-level giant-atom setup, it is of great interest that, the Autler-Townes splitting is dramatically modulated by the giant atom, in which the width of the transmission valleys (reflection range) is tunable in terms of the atomic size. Our investigation will be beneficial to the photon or phonon control in quantum network based on mesoscopical or even macroscopical quantum nodes involving the giant atom.