Optical properties of small particle composites: theories and applications

Conference · Sun Jan 01 04:00:00 EST 1978 · AIP (Am. Inst. Phys.) Conf. Proc.; (United States)

OSTI ID:6627161

Lamb, W; Wood, D M; Ashcroft, N W

The problem of calculating the optical properties of an assembly of small metallic spheres (radius a) dispersed in a dielectric host is approached from the standpoint of multiple scattering theory as formulated for scalar fields and periodic systems by Morse. If k is the largest wave vector of the radiation in either the bulk constituent or in the composite, the leading term for the dielectric function in the limit ka ..-->.. 0 emerges as the Maxwell-Garnett result. The result is subject to significant modification, however, if structure in the composite large on the scale of a wavelength (e.g. clustering or periodicity in the dilute limit) is present. For both Maxwell-Garnett and effective medium theories the effects of introducing a third component in the form of an insulator coating (spatially correlated, therefore, to the metallic component) are examined, particularly in the frequency dependent reflectivity. Finally, an argument is given for the two component system which leads to the Maxwell-Garnett result from consideration of an effective medium approach for insulator-coated metallic inclusions, these properly reflecting the topology of such composites. For m(>2) component systems an expression for the effective dielectric function is derived by applying a similar argument.

• Research Organization: Cornell Univ., Ithaca, NY
• OSTI ID: 6627161
• Report Number(s): CONF-770925-
• Conference Information: Journal Name: AIP (Am. Inst. Phys.) Conf. Proc.; (United States) Journal Volume: 40
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ELEMENTS
METALS
MICROSPHERES
MULTIPLE SCATTERING
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
REFLECTIVITY
SCATTERING
SURFACE PROPERTIES