Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: High efficiency dielectric metasurfaces at visible wavelengths   Metasurfaces are planar optical elements that hold promise for overcoming the
limitations of refractive and conventional diffractive optics1-3. Dielectric
metasurfaces demonstrated thus far4-10 are limited to transparency windows at
infrared wavelengths because of significant optical absorption and loss at
visible wavelengths. It is critical that new materials and fabrication
techniques be developed for dielectric metasurfaces at visible wavelengths to
enable applications such as three-dimensional displays, wearable optics and
planar optical systems11. Here, we demonstrate high performance titanium
dioxide dielectric metasurfaces in the form of holograms for red, green and
blue wavelengths with record absolute efficiency (>78%). We use atomic layer
deposition of amorphous titanium dioxide that exhibits low surface roughness of
0.738 nm and ideal optical properties. To fabricate the metasurfaces we use a
lift-off-like process that allows us to produce highly anisotropic nanofins
with shape birefringence. This process is applicable to any optical element and
can be implemented using a broad class of materials.

32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg