Nonlinear Control of Tunneling Through an Epsilon-Near-Zero Channel

TL;DR

This paper demonstrates experimental nonlinear control of epsilon-near-zero tunneling in waveguides, enabling tunable wave transmission and potential applications in sensing and slow-light devices.

Contribution

It introduces a practical method for nonlinear and self-modulation control of ENZ tunneling using a diode with tunable capacitance.

Findings

Successful experimental control of ENZ tunneling with external fields

Demonstration of self-modulation of transmission resonance

Potential for tunable slow-light and sensing applications

Abstract

The epsilon-near-zero (ENZ) tunneling phenomenon allows full transmission of waves through a narrow channel even in the presence of a strong geometric mismatch. Here we experimentally demonstrate nonlinear control of the ENZ tunneling by an external field, as well as self-modulation of the transmission resonance due to the incident wave. Using a waveguide section near cut-off frequency as the ENZ system, we introduce a diode with tunable and nonlinear capacitance to demonstrate both of these effects. Our results confirm earlier theoretical ideas on using an ENZ channel for dielectric sensing, and their potential applications for tunable slow-light structures.