Equivalent refractive index of multilayer films of different materials

Sharma, Shiv K. ; Yadava, V. N. ; Chopra, K. L. (1974) Equivalent refractive index of multilayer films of different materials Thin Solid Films, 20 (2). pp. 209-215. ISSN 0040-6090

Full text not available from this repository.

Official URL: http://linkinghub.elsevier.com/retrieve/pii/004060...

Related URL: http://dx.doi.org/10.1016/0040-6090(74)90056-X


The variation of the equivalent refractive index with composition of multilayer films of ZnS-MgF2-SiO, ZnS-Na3AlF6 and Ge-ZnS, prepared by depositing alternate layers of different materials, has been investigated. It has been established that, for small step thicknesses (much less than the wavelength of light to be used for measurements) of each layer, the composite multilayer films are optically equivalent to homogeneously mixed films of the same materials of corresponding relative compositions. Further, the results show that the indices of the multilayer films of ZnS-MgF2-SiO and ZnS-Na3AlF6 are in good agreement with the values predicted on the basis of the Lorentz-Lorenz theory. The refractive index of Ge-ZnS multilayer films is in agreement with the Drude theory. Our studies also show that the refractive index of a multilayer film composed of three materials, two of which react chemically in the molten and vapour states, as, for example, ZnS and SiO in ZnS-MgF2-SiO films, is equivalent to that expected theoretically for a homogeneously mixed film of the same materials. The controlled and predictable equivalent behaviour of multilayer films suggests their use to produce variable refractive index optical coatings by selecting any number of materials which may or may not react with each other chemically.

Item Type:Article
Source:Copyright of this article belongs to Elsevier Science.
ID Code:23130
Deposited On:25 Nov 2010 13:29
Last Modified:28 May 2011 10:04

Repository Staff Only: item control page