# The Finitely Conducting Lamellar Diffraction Grating

Botten 1981: Generalises the modal formalism to lamellar gratings made of a finitely conducting material. Loss makes the eigenvalue problem…

Canonical: https://mcgrating.com/publications/botten-1981-finitely-conducting-lamellar-grating.html


L.C. Botten, M.S. Craig, R.C. McPhedran, J.L. Adams, J.R. Andrewartha

L.C. Botten, M.S. Craig, R.C. McPhedran, J.L. Adams and J.R. Andrewartha, “The Finitely Conducting Lamellar Diffraction Grating”, Optica Acta: International Journal of Optics **28**, 1087-1102 (1981). [https://doi.org/10.1080/713820680](https://doi.org/10.1080/713820680)

Generalises the modal formalism to lamellar gratings made of a finitely conducting material. Loss makes the eigenvalue problem non-self-adjoint, so the modes are complex and no longer orthogonal in the simple sense; the paper shows how the expansion and the matching still go through, and gives results for cases the integral-equation methods of the time could not handle.

Lossy metallic lamellar gratings in Modal Collinear are treated this way.

**Implemented in**: [Modal Collinear](https://mcgrating.com/products.html#modal-collinear)

**Cited on**: [The modal method (RCWA / FMM)](https://mcgrating.com/features/modal-method.html)

**Bibliography**: [Reference [6]](https://mcgrating.com/references.html#ref-6)

**Full text**: [The Finitely Conducting Lamellar Diffraction Grating](https://mcgrating.com/references/ref06.pdf) (PDF, 577 KB)

© 1981 Informa UK Limited. This copy is hosted for the convenience of MC Grating users; the version of record is the publisher's, at the DOI above.

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