$\Lambda$-Type Giant Atom Mediated Controllable Single-Photon Transport in a One-Dimensional Chiral Waveguide

TL;DR

This paper studies how a driven $$-type giant atom coupled to a 1D chiral waveguide can be used to control single-photon transport, revealing tunable spectral features and switching capabilities in both Markovian and non-Markovian regimes.

Contribution

It provides analytical solutions for single-photon scattering in a driven giant atom system with chiral coupling, highlighting controllable spectral splitting and transport switching.

Findings

External driving causes spectral dip splitting.

Chiral coupling enables switching between transmission and reflection.

Giant atom size influences non-Markovian spectral oscillations.

Abstract

We investigate the single-photon scattering spectrum of a driven $\Lambda$-type giant atom system chirally coupled to a one-dimensional (1D) waveguide. By employing a real-space scattering approach, we obtain analytical solutions for the scattering amplitudes that remain valid in both Markovian and non-Markovian regimes. We observe that an external driving field induces a splitting of the transmission spectrum's dip into double dips, with the distance between the two dips increasing as the strength of the driving field increases. The chiral nature of the coupling allows for controlled switching between complete transmission and perfect reflection of incident photons. In the Markovian limit, we predict robust perfect transmission at specific phase values, independent of the driving field parameters.Moreover, in the non-Markovian regime, as the size of the giant atom increases, the oscillatory behavior of the scattering spectrum becomes more pronounced. Adjusting the giant atom size enables control over the number of decoupling points as well as the number of complete reflection points.