TY  - JOUR
A1  - Polley, Nabarun
A1  - Werner, Peter
A1  - Balderas-Valadez, Ruth Fabiola
A1  - Pacholski, Claudia
T1  - Bottom, top, or in between
BT  - combining plasmonic nanohole arrays and hydrogel microgels for optical fiber snsor applications
JF  - Advanced materials interfaces
N2  - Attractive label-free plasmonic optical fiber sensors can be developed by cleverly choosing the arrangement of plasmonic nanostructures and other building blocks. Here, the final response depends very much on the alignment and position (stacking) of the individual elements. In this work, three different types of fiber optic sensing geometries fabricated by simple layer-by-layer stacking are presented, consisting of stimulus-sensitive poly-N-isopropylacrylamide (polyNIPAM) microgel arrays and plasmonic nanohole arrays (NHAs), namely NHA/polyNIPAM, polyNIPAM/NHA, polyNIPAM/NHA/polyNIPAM. Their optical response to a representative stimulus, namely temperature, is investigated. NHA/polyNIPAM monitors the volume phase transition of polyNIPAM microgels through changes in the spectral position and the amplitude of the reflection minimum of plasmonic NHA. In contrast, polyNIPAM/NHA shows a more complex response to the swelling and collapse of polyNIPAM microgels in their reflectance spectra. The most pronounced changes in optical response are observed by monitoring the amplitude of the reflectance minimum of this sensor during heating/cooling cycles. Finally, the triple stack of polyNIPAM/NHA/polyNIPAM at the end of a optical fiber tip combines the advantages of the NHA/polyNIPAM, polyNIPAM/NHA double stacks for optical sensing. The unique layer-by-layer stacking of microgel and nanostructure is customizable and can be easily adopted for other applications.
KW  - bottom-up fabrication
KW  - layer-by-layer stacking
KW  - microgel arrays
KW  - optical
KW  - fiber sensors
KW  - plasmonic nanohole arrays
Y1  - 2022
U6  - https://doi.org/10.1002/admi.202102312
SN  - 2196-7350
VL  - 9
IS  - 15
PB  - Wiley
CY  - Hoboken
ER  -