Organo-lanthanide complexes as luminescent dopants in polymer waveguides fabricated by hot embossing S. Moynihan a , R. Van Deun b , K. Binnemans b , J. Krueger c , G. von Papen c , A. Kewell c , G. Crean c , G. Redmond a, * a Nanotechnology Group, Tyndall National Institute, Lee Maltings, Prospect Row, Cork, Ireland b Department of Chemistry, K.U. Leuven, Celestijnenlaan 200F, B-3001 Heverlee (Leuven), Belgium c Nanocomms Ltd., 9 Mardyke Parade, Cork, Ireland Received 31 May 2006; received in revised form 25 September 2006; accepted 11 October 2006 Available online 11 December 2006 Abstract Lanthanide complexes, Eu(dbm) 3 (Phen) and Er(dbm) 3 (Phen), are employed as luminescent dopants within polymer channel wave- guide devices fabricated by hot embossing. Spectroscopic properties of the complexes as dopants in the waveguide core polymer are investigated in detail. Judd–Ofelt parameters are calculated for the europium chelate and radiative properties are determined viz. poten- tial for optical amplification. Channel waveguides fabricated by single level embossing are shown to be capable of guiding visible and infrared light emitted following optical excitation of the dopants. Multi-level polymer micro-optical benches incorporating doped chan- nel waveguides and passive locational features for self-alignment and integration of optical fibres are fabricated in a multi-level single- step embossing process and are shown to successfully out-couple the waveguided dopant emission. Ó 2006 Elsevier B.V. All rights reserved. PACS: 78.20.e; 42.82.Et; 81.05.Lg; 42.70.Jk Keywords: Lanthanide complex; Europium; Erbium; Photoluminescence; Polymer waveguide; Hot embossing 1. Introduction In the field of optical telecommunications, lanthanide doped inorganic devices, e.g., erbium doped fibre amplifiers (EDFAs), are routinely employed to overcome losses in long haul silica fibre transmission systems. Also, recent improvements in the propagation loss characteristics of plastic optical fibre (POF) at visible wavelengths, combined with its low cost, high flexibility and large core size, which facilitates fibre interconnection, has made POF particularly attractive for use in metro, access and local area networks. As a result, the development of plastic optical fibre ampli- fiers for signal regeneration within data communications networks is also underway [1,2]. Both types of fibre ampli- fiers may, however, exploit path lengths of several meters for amplification. In the future, a need is foreseen for chip-level monolithic photonic systems that integrate vari- ous functions such as optical multiplexing, switching, mod- ulation and amplification. Ideally, these systems should employ waveguide based optical amplifiers operating across the visible and near infrared spectral range to com- pensate for optical losses [3]. However, on-chip device inte- gration is very spatially restrictive, typically allowing an optical path length of only a few centimetres. Conse- quently, substantial optimisation of materials and pro- cesses for the realisation of waveguide based optical amplification is now required. In terms of waveguide materials and fabrication pro- cesses, polymers have attracted significant attention due to relatively low costs, favourable materials properties and potential ease of volume processing using methods 0925-3467/$ - see front matter Ó 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.optmat.2006.10.010 * Corresponding author. E-mail address: gareth.redmond@tyndall.ie (G. Redmond). www.elsevier.com/locate/optmat Optical Materials 29 (2007) 1798–1808