Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improving Magnetic Resonance Imaging with Smart and Thin Metasurfaces   Over almost five decades of development and improvement, Magnetic Resonance
Imaging (MRI) has become a rich and powerful, non-invasive technique in medical
imaging, yet not reaching its physical limits. Technical and physiological
restrictions constrain physically feasible developments. A common solution to
improve imaging speed and resolution is to use higher field strengths, which
also has subtle and potentially harmful implications. However, patient safety
is to be considered utterly important at all stages of research and clinical
routine. Here we show that dynamic metamaterials are a promising solution to
expand the potential of MRI and to overcome some limitations. A thin, smart,
non-linear metamaterial is presented that enhances the imaging performance and
increases the signal-to-noise ratio in 3T MRI significantly (up to eightfold),
whilst the transmit field is not affected due to self-detuning and, thus,
patient safety is also assured. This self-detuning works without introducing
any additional overhead related to MRI-compatible electronic control components
or active (de-)tuning mechanisms. The design paradigm, simulation results,
on-bench characterization, and MRI experiments using homogeneous and structural
phantoms are described. The suggested single-layer metasurface paves the way
for conformal and patient-specific manufacturing, which was not possible before
due to typically bulky and rigid metamaterial structures.

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The categories of this paper are: q-alg
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The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
11
The categories of this paper are: hep-lat
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
0
The categories of this paper are: hep-ph
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The categories of this paper are: stat
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The categories of this paper are: cond-mat
2
The categories of this paper are: math
18
The categories of this paper are: econ