Enhancement of adsorbate vibrations due to interaction with microcavity mode in porous silicon superlattice

A porous silicon Fabry-Perot microcavity centred in the infrared region was used, after exposure to dodecane (C12H26) vapour, to study the interaction of the cavity mode with the C-H vibrations of the adsorbed molecules inside pores. This Fabry-Perot microcavity has been realised by controlling the current and the time of a stepwise anodization procedure of a p(+)-type silicon wafer in an electrochemical cell with a hydrofluoric acid solution. Splitting of the cavity mode dispersion curve (frequency versus wavevector) acid enhancement of the infrared absorption of the adsorbate bands have been studied for various concentrations of dodecane. (C) 1999 Elsevier Science B.V. All rights reserved.