Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Single-electron charging of self-assembled InAs quantum dots   The many-particle ground state and excitations of self-assembled InAs quantum
dots are investigated using far-infrared (FIR) and capacitance spectroscopy.
The contributions of quantization and charging energies to the $n$--electron
energy spectrum are determined. For $n = 1$, 2, we find good agreement with a
parabolic model; for higher filling, the Coulomb interaction reveals itself not
only in the capacitance, but also in the FIR excitations

15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg