Frequency tunable single photon diode based on giant atom coupling to a waveguide

Area of Science:

• Quantum Optics
• Atomic Physics
• Photonics

Background:

• Investigating single photon scattering properties is crucial for developing quantum technologies.
• Giant atoms interacting with waveguides offer unique platforms for controlling quantum states.
• Nonreciprocal devices are essential components in photonic circuits for signal routing.

Purpose of the Study:

• To theoretically investigate single photon scattering properties in a waveguide coupled to a giant atom with a three-level system.
• To determine the conditions for achieving perfect single photon nonreciprocal scattering in both Markovian and non-Markovian regimes.
• To explore the realization of a frequency-tunable single photon diode.

Main Methods:

• Theoretical analysis of single photon scattering.
• Derivation of analytical expressions for single photon scattering amplitudes.
• Investigation of a giant atom with a three-level system coupled to a waveguide at two points and driven by a classical field.

Main Results:

• Identified parameters for perfect single photon nonreciprocal scattering in the Markovian regime, including external classical field, energy dissipation, coupling strength phase difference, and accumulated phase.
• Demonstrated that perfect non-reciprocity is achievable in the non-Markovian regime despite increased complexity due to time delay.
• Showcased the ability to switch nonreciprocity by controlling the classical field for resonant photons and achieve perfect non-reciprocal transmission for non-resonant photons by adjusting Rabi frequency.

Conclusions:

• The study provides a theoretical framework for realizing perfect single photon nonreciprocal scattering.
• The proposed system offers a method for creating a frequency-tunable single photon diode.
• This research contributes to the development of advanced quantum optical devices and components.