Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Approaching the upper limits of the local density of states via
  optimized metallic cavities   By computational optimization of air-void cavities in metallic substrates, we
show that the local density of states (LDOS) can reach within a factor of
$\approx 10$ of recent theoretical upper limits, and within a factor $\approx
4$ for the single-polarization LDOS, demonstrating that the theoretical limits
are nearly attainable. Optimizing the total LDOS results in a spontaneous
symmetry breaking where it is preferable to couple to a specific polarization.
Moreover, simple shapes such as optimized cylinders attain nearly the
performance of complicated many-parameter optima, suggesting that only one or
two key parameters matter in order to approach the theoretical LDOS bounds for
metallic resonators.

12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
29
The categories of this paper are: funct-an