Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nanoscale multifunctional sensor formed by a Ni nanotube and a scanning
  Nb nanoSQUID   Nanoscale magnets might form the building blocks of next generation memories.
To explore their functionality, magnetic sensing at the nanoscale is key. We
present a multifunctional combination of a scanning nanometer-sized
superconducting quantum interference device (nanoSQUID) and a Ni nanotube
attached to an ultrasoft cantilever as a magnetic tip. We map out and analyze
the magnetic coupling between the Ni tube and the Nb nanoSQUID, demonstrate
imaging of an Abrikosov vortex trapped in the SQUID structure - which is
important in ruling out spurious magnetic signals - and reveal the high
potential of the nanoSQUID as an ultrasensitive displacement detector. Our
results open a new avenue for fundamental studies of nanoscale magnetism and
superconductivity.

25
The categories of this paper are: patt-sol
6
The categories of this paper are: astro-ph
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
13
The categories of this paper are: quant-ph
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat