Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Direct Rashba spin-orbit interaction in Si and Ge nanowires with
  different growth directions
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
25
The categories of this paper are: patt-sol
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin