Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electromagnetic induction imaging with atomic magnetometers: unlocking
  the low-conductivity regime   Electromagnetic induction imaging with atomic magnetometers has disclosed
unprecedented domains for imaging, from security screening to material
characterization. However, applications to low-conductivity specimens -- most
notably for biomedical imaging -- require sensitivity, stability, and
tunability only speculated thus far. Here, we demonstrate contactless and
non-invasive imaging down to 50 S/m using a 50 fT/Hz$^{-1/2}$ $^{87}$Rb
radio-frequency atomic magnetometer operating in an unshielded environment and
near room temperature. Two-dimensional images of test objects are obtained with
a near-resonant imaging approach, which reduces the phase noise by a factor
172, with projected sensitivity of 1 S/m. Our results, an improvement of more
than three orders of magnitude on previous imaging demonstrations, push
electromagnetic imaging with atomic magnetometers to regions of interest for
semiconductors, insulators, and biological tissues.

22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
27
The categories of this paper are: comp-gas