Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Giant Quantum Reflection of Neon Atoms from a Ridged Silicon Surface   The specular reflectivity of slow, metastable neon atoms from a silicon
surface was found to increase markedly when the flat surface was replaced by a
grating structure with parallel narrow ridges. For a surface with ridges that
have a sufficiently narrow top, the reflectivity was found to increase more
than two orders of magnitude at the incident angle of 10 mRad from the surface.
The slope of the reflectivity vs the incident angle near zero was found to be
nearly an order of magnitude smaller than that of a flat surface. A grating
with 6.5% efficiency for the first-order diffraction was fabricated by using
the ridged surface structure.

13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ