Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing phonon softening in ferroelectrics by the scanning probe
  microwave spectroscopy   Microwave measurements have recently been successfully applied to measure
ferroelectric materials on the nanoscale, including detection of polarization
switching and ferroelectric domain walls. Here we discuss the question whether
scanning probe microscopy (SPM) operating at microwave frequency can identify
the changes associated with the soft phonon dynamics in a ferroic. The
analytical expressions for the electric potential, complex impedance and
dielectric losses are derived and analyzed, since these physical quantities are
linked to experimentally-measurable properties of the ferroic. As a ferroic we
consider virtual or proper ferroelectric with an optic phonon mode that softens
at a Curie point. We also consider a decay mechanism linked to the conductance
of the ferroic, and thus manifesting itself as the dielectric loss in the
material. Our key finding is that the influence of the soft phonon dispersion
on the surface potential distribution, complex impedance and dielectric losses
are evidently strong in the vicinity (10-30 K) of the Curie temperature.
Furthermore, we quantified how the spatial distribution and frequency spectra
of the complex impedance and the dielectric losses react on the dynamics of the
soft phonons near the Curie point. These results set the stage for
characterization of polar phase transitions with nanoscale microwave
measurements, providing a complementary approach to well established
electromechanical measurements for fundamental understanding of ferroelectric
properties as well as their applications in telecommunication and computing.

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The categories of this paper are: hep-th
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The categories of this paper are: q-fin
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The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
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The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
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The categories of this paper are: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-th
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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: math
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: stat
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The categories of this paper are: ao-sci