Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Behavior of colloidal particles at an air/nematic liquid crystal
  interface   We examine the behavior of spherical silica particles trapped at an
air-nematic liquid crystal interface. When a strong normal anchoring is
imposed, the beads spontaneously form various structures depending on their
area density and the nematic thickness. Using optical tweezers, we determine
the pair potential and explain the formation of these patterns. The energy
profile is discussed in terms of capillary and elastic interactions. Finally,
we detail the mechanisms that control the formation of an hexagonal lattice and
analyze the role of gravity for curved interfaces.

28
The categories of this paper are: alg-geom
31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
19
The categories of this paper are: eess
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int