Electromagnetically induced absorption in detuned stub waveguides: a simple analytical and experimental model

Area of Science:

• * Electromagnetism and Optics
• * Condensed Matter Physics
• * Wave Phenomena

Background:

• * Electromagnetic Induced Absorption (EIA) is a quantum interference effect.
• * Classical analogues are sought for practical device applications.
• * Photonic devices with stubs offer tunable resonant properties.

Purpose of the Study:

• * To demonstrate a classical analogue of EIA in a waveguide with two stubs.
• * To analytically and experimentally investigate the role of stub length detuning.
• * To explore potential applications in integrated photonic devices.

Main Methods:

• * Analytical derivation using the Green's function method.
• * Experimental validation using radio-frequency coaxial cables.
• * Modeling the system as two coupled radiative resonators.

Main Results:

• * Destructive interference between stubs creates sharp, high-Q resonances in transmission and absorption.
• * Transmission coefficient exhibits Fano-like behavior, with parameters dependent on stub detuning (δ).
• * Absorption peaks at a specific detuning value, influenced by waveguide losses.

Conclusions:

• * The demonstrated classical EIA analogue is tunable via stub length detuning.
• * The findings are crucial for designing integrated devices like narrow-frequency filters and high-speed switches.
• * This work bridges quantum interference phenomena with classical device engineering.