Nanoparticle gratings for compact spectrometers: an application of photovoltaic tweezers

Abstract

Compact spectrometers are useful in fiber-based setups, portable devices or systems where weight and space are limited. On the other side, Photovoltaic Tweezers (PVT) are a simple and flexible optoelectronic technique for patterning and trapping nano- and microobjects in accordance with arbitrary light profiles. In this work, Al nanoparticle (NP) gratings assembled by PVT have been used for the fabrication of SWIFTS-based and dispersive spectrometers. A method for transferring the NP structures has been successfully adapted to deposit these gratings on top of Ti-diffused LiNbO3 wavguides (WG) without a significant loss of quality; the successful transference of NP patterns to arbitrary substrates remarkably extends the potential applications of PVT.