Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Frequency-independent terahertz anomalous Hall effect in DyCo$_{5}$,
  Co$_{32}$Fe$_{68}$ and Gd$_{27}$Fe$_{73}$ thin films from DC to 40 THz   The anomalous Hall effect (AHE) is a fundamental spintronic
charge-to-charge-current conversion phenomenon and closely related to
spin-to-charge-current conversion by the spin Hall effect. Future high-speed
spintronic devices will crucially rely on such conversion effects at terahertz
(THz) frequencies. Here, we reveal that the AHE remains operative from DC up to
40 THz with a flat frequency response in thin films of three technologically
relevant magnetic materials: DyCo$_{5}$, Co$_{32}$Fe$_{68}$ and
Gd$_{27}$Fe$_{73}$. We measure the frequency-dependent conductivity-tensor
elements ${\sigma}_{xx}$ and ${\sigma}_{yx}$ and find good agreement with DC
measurements. Our experimental findings are fully consistent with ab-initio
calculations of ${\sigma}_{yx}$ for CoFe and highlight the role of the large
Drude scattering rate (~100 THz) of metal thin films, which smears out any
sharp spectral features of the THz AHE. Finally, we find that the intrinsic
contribution to the THz AHE dominates over the extrinsic mechanisms for the
Co$_{32}$Fe$_{68}$ sample. The results imply that the AHE and related effects
such as the spin Hall effect are highly promising ingredients of future THz
spintronic devices reliably operating from DC to 40 THz and beyond.

8
The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas