Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On-chip label-free plasmonic based imaging microscopy for microfluidics   In this work, we demonstrated on-chip label-free imaging microscopy using
real and Fourier Plane (FP) microscopic dark field images of Surface Plasmons
(SP), excited on engineered 1D and 2D low aspect ratio periodic plasmonic
nanostructures. The periodic plasmonic nanostructures with period almost equal
to resonance wavelength, were engineered to exhibit transmission resonances as
transmission peaks in visible spectrum at normal incidence, without using
extraordinary optical transmission phenomena. The plasmonic nanostructures
exhibited a polarization rotation of 90 degree mediated by differential phase
retardation in the SP mode due to Transverse Electric and Magnetic components.
This was used to develop a dark field on-chip plasmonic polarization microscope
for imaging SP excitation in real and Fourier planes. After successful
integration of these plasmonic nanostructures with SU- 8 based microfluidic
channels, a real-time monitoring of label free on chip sensing was
demonstrated. Label-free on-chip imaging for interface of colorless miscible
and immiscible analytes flowing on plasmonic nanostructures in the microfluidic
channels were performed using color-selective filtering nature of plasmonic
nanostructures. Since the imaging is realized on a chip and does not need any
complicated and bulky arrangement, it will be well suited for on-chip point of
care diagnostics.

18
The categories of this paper are: econ
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
29
The categories of this paper are: funct-an
8
The categories of this paper are: hep-ex
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
1
The categories of this paper are: cs
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph