Gain and loss enhancement in active and passive particulate composite materials

TL;DR

This paper establishes conditions under which blending active or dissipative dielectric materials enhances gain or loss in homogenized composite materials, using the Bruggeman formalism.

Contribution

It provides the first theoretical criteria for gain and loss enhancement in composite materials based on dielectric properties.

Findings

Gain/loss enhancement occurs when imaginary parts are similar and real parts are dissimilar.

Conditions are derived using the Bruggeman homogenization formalism.

The results guide the design of composites with tailored electromagnetic properties.

Abstract

Two active dielectric materials may be blended together to realize a homogenized composite material (HCM) which exhibits more gain than either component material. Likewise, two dissipative dielectric materials may be blended together to realize an HCM which exhibits more loss than either component material. Sufficient conditions for such gain/loss enhancement were established using the Bruggeman homogenization formalism. Gain/loss enhancement arises when (i) the imaginary parts of the relative permittivities of both component materials are similar in magnitude and (ii) the real parts of the relative permittivities of both component materials are dissimilar in magnitude.