Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Complex temperature dependence of coupling and dissipation of
  cavity-magnon polaritons from milliKelvin to room temperature   Hybridized magnonic-photonic systems are key components for future
information processing technologies such as storage, manipulation or conversion
of data both in the classical (mostly at room temperature) and quantum
(cryogenic) regime. In this work, we investigate a YIG sphere coupled strongly
to a microwave cavity over the full temperature range from $290\,\mathrm{K}$
down to $30\,\mathrm{mK}$. The cavity-magnon polaritons are studied from the
classical to the quantum regime where the thermal energy is less than one
resonant microwave quanta, i.e. at temperatures below $1\,\mathrm{K}$. We
compare the temperature dependence of the coupling strength $g_{\rm{eff}}(T)$,
describing the strength of coherent energy exchange between spin ensemble and
cavity photon, to the temperature behavior of the saturation magnetization
evolution $M_{\rm{s}}(T)$ and find strong deviations at low temperatures. The
temperature dependence of magnonic disspation is governed at intermediate
temperatures by rare earth impurity scattering leading to a strong peak at
$40\,$K. The linewidth $\kappa_{\rm{m}}$ decreases to $1.2\,$MHz at $30\,$mK,
making this system suitable as a building block for quantum electrodynamics
experiments. We achieve an electromagnonic cooperativity in excess of $20$ over
the entire temperature range, with values beyond $100$ in the milliKelvin
regime as well as at room temperature. With our measurements, spectroscopy on
strongly coupled magnon-photon systems is demonstrated as versatile tool for
spin material studies over large temperature ranges. Key parameters are
provided in a single measurement, thus simplifying investigations
significantly.

37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
7
The categories of this paper are: hep-th
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys