Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ultrafast carrier thermalization in lead iodide perovskite probed with
  two-dimensional electronic spectroscopy   In band-like semiconductors, charge carriers form a thermal energy
distribution rapidly after optical excitation. In hybrid lead halide
perovskites, the cooling of such thermal carrier distributions occurs on
timescales of ~300 fs via carrier-phonon scattering. However, the initial
build-up of the thermal distribution proved difficult to resolve with
pump-probe techniques due to the requirement of high resolution, both in time
and in energy. Here, we use two-dimensional electronic spectroscopy with
sub-10fs resolution to directly observe the carrier interactions that lead to
the formation of a thermal carrier distribution. We find that thermalization
occurs dominantly via carrier-carrier scattering under the investigated
fluences and report the dependence of carrier scattering rates on excess energy
and carrier density. We extract characteristic carrier thermalization times
from below 10 fs to 85 fs. These values allow for mobilities of up to 500 cm^2
V^(-1) s^(-1) at carrier densities lower than 2x10^19 cm^(-3) and limit the
time for carrier extraction in hot carrier solar cells.

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The categories of this paper are: solv-int
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The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
18
The categories of this paper are: econ
3
The categories of this paper are: physics
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex