Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Selective reflection from Rb layer with thickness below $\lambda$/12 and
  applications   We have studied the peculiarities of selective reflection from Rb vapor cell
with thickness $L <$ 70 nm, which is over an order of magnitude smaller than
the resonant wavelength for Rb atomic D$_1$ line $\lambda$ = 795 nm. A huge
($\approx$ 240 MHz) red shift and spectral broadening of reflection signal is
recorded for $L =$ 40 nm caused by the atom-surface interaction. Also
completely frequency resolved hyperfine Paschen-Back splitting of atomic
transitions to four components for $^{87}$Rb and six components for $^{85}$Rb
is recorded in strong magnetic field ($B >$ 2 kG).

21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn