Single mode waveguide platform for spontaneous and surface-enhanced on-chip Raman spectroscopy

Abstract

We review an on-chip approach for spontaneous Raman spectroscopy and surface-enhanced Raman spectroscopy based on evanescent excitation of the analyte aswell as evanescent collection of the Raman signal using complementary metal oxide semiconductor (CMOS)-compatible single modewaveguides. The signal is either directly collected fromthe analyte molecules or via plasmonic nanoantennas integrated on top of thewaveguides. Flexibility in the design of the geometry of the waveguide, and/or the geometry of the antennas, enables optimization of the collection efficiency. Furthermore, the sensor can be integrated with additional functionality (sources, detectors, spectrometers) on the same chip. In this paper, the basic theoretical concepts are introduced to identify the key design parameters, and some proof-of-concept experimental results are reviewed.