Chapter 13
Spectroscopic Aspects
of Polydimethylsiloxane (PDMS)
Used for Optical Waveguides
Dengke Cai and H. Michael Heise
Abstract Polydimethylsiloxane polymers were studied for their suitability in
optical waveguides. Optical constants of core and clad materials have been measured within the visible and near-infrared spectral range. The absorption loss of
PDMS in the datacom region of 600–1600 nm is mainly caused by scattering loss
and attenuation by overtone and combination band vibrations of CH containing
groups. Based on observed positions of those fundamental, overtone and combination bands and their vibrational assignment, normal vibration frequencies and
anharmonicity constants were determined. An empirical correlation between integral band strength and intrinsic absorption loss was derived based on the vibrational
spectra of the two materials, providing also estimates for deuterated and halogenated PDMS materials with even lower absorption losses. Besides intrinsic
material attenuation, also extrinsic losses from waveguide fabrication have been
investigated. Furthermore, multimode waveguides were fabricated with an insertion
loss of 0.05 dB/cm at the most frequently applied data communication wavelength
of 850 nm. Effects of accelerated ageing have been assessed for the optical characteristics of PDMS materials.
13.1 Introduction
Next-generation Internet switches and high-end computers are expected to process
aggregate data rates in the order of Tbit/s. Consequently, the interconnections
between the processing units will have to handle data rates in the order of 10–40
D. Cai
Laboratory of Micro-Structure Technology, Department of Electrical
Engineering and Information Technology, TU Dortmund University,
44227 Dortmund, Germany
H. M. Heise (&)
Interdisciplinary Center for Life Sciences, South-Westphalia University
of Applied Sciences, Frauenstuhlweg 31, 58644 Iserlohn, Germany
e-mail: heise.h@fh-swf.de
© Springer Nature Switzerland AG 2019
A. Koleżyński and M. Król (eds.), Molecular Spectroscopy—Experiment
and Theory, Challenges and Advances in Computational Chemistry
and Physics 26, https://doi.org/10.1007/978-3-030-01355-4_13
401
Spectroscopic Aspects
of Polydimethylsiloxane (PDMS)
Used for Optical Waveguides
Dengke Cai and H. Michael Heise
Abstract Polydimethylsiloxane polymers were studied for their suitability in
optical waveguides. Optical constants of core and clad materials have been measured within the visible and near-infrared spectral range. The absorption loss of
PDMS in the datacom region of 600–1600 nm is mainly caused by scattering loss
and attenuation by overtone and combination band vibrations of CH containing
groups. Based on observed positions of those fundamental, overtone and combination bands and their vibrational assignment, normal vibration frequencies and
anharmonicity constants were determined. An empirical correlation between integral band strength and intrinsic absorption loss was derived based on the vibrational
spectra of the two materials, providing also estimates for deuterated and halogenated PDMS materials with even lower absorption losses. Besides intrinsic
material attenuation, also extrinsic losses from waveguide fabrication have been
investigated. Furthermore, multimode waveguides were fabricated with an insertion
loss of 0.05 dB/cm at the most frequently applied data communication wavelength
of 850 nm. Effects of accelerated ageing have been assessed for the optical characteristics of PDMS materials.
13.1 Introduction
Next-generation Internet switches and high-end computers are expected to process
aggregate data rates in the order of Tbit/s. Consequently, the interconnections
between the processing units will have to handle data rates in the order of 10–40
D. Cai
Laboratory of Micro-Structure Technology, Department of Electrical
Engineering and Information Technology, TU Dortmund University,
44227 Dortmund, Germany
H. M. Heise (&)
Interdisciplinary Center for Life Sciences, South-Westphalia University
of Applied Sciences, Frauenstuhlweg 31, 58644 Iserlohn, Germany
e-mail: heise.h@fh-swf.de
© Springer Nature Switzerland AG 2019
A. Koleżyński and M. Król (eds.), Molecular Spectroscopy—Experiment
and Theory, Challenges and Advances in Computational Chemistry
and Physics 26, https://doi.org/10.1007/978-3-030-01355-4_13
401