Electromagnetic energy stored in inhomogeneous scattering systems

Author(s)

Arruda, Tiago J. ^[1] ; Pinheiro, Felipe A. ^[2] ; Martinez, Alexandre S. ^{[3, 4]}

Affiliation

^[1] Univ Sao Paulo, Inst Fis Sao Carlos, BR-13566590 Sao Carlos, SP - Brazil

^[2] Univ Fed Rio de Janeiro, Inst Fis, BR-21941972 Rio De Janeiro, RJ - Brazil

^[3] Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14040901 Ribeirao Preto, SP - Brazil

^[4] Natl Inst Sci & Technol Complex Syst, BR-22290180 Rio De Janeiro, RJ - Brazil

• Document type: Journal article
• Source: JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION; v. 34, n. 10, p. 1934-1939, OCT 1 2017.
• Web of Science Citations: 2

Abstract

We analytically study the time-averaged electromagnetic energy stored inside scatterers containing inclusions of arbitrary shapes. Assuming the low density of inclusions, we derive the expression for the energy-transport velocity through disordered media without relying on the radiative transfer equation. Moreover, this expression is independent of the shape of scatterers. In addition, we obtain a relation between the dwell and absorption times associated with inclusions by considering the relationship between the internal energy and absorption cross-section. An approximation for the electromagnetic energy stored inside a disordered medium in terms of the transport mean free path and the packing fraction is also derived. This expression suggests that the enhanced electromagnetic energy within the host medium is achieved for inclusions exhibiting negative scattering asymmetry parameters. As a result, disordered media with enhanced backscattering is expected to exhibit large quality factors. (C) 2017 Optical Society of America (AU)

• FAPESP's process: 15/21194-3 - Interaction between atoms and metamaterials: Purcell effect and effective medium theories
• Grantee: Tiago José Arruda
• Support type: Scholarships in Brazil - Post-Doctorate