Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Temperature induced spin coherence dissipation in quantum dots   The temperature dependence of electron spin coherence in singly negatively
charged (In,Ga)As/GaAs quantum dots is studied by time-resolved Faraday
rotation. The decoherence time T2 is constant on a microsecond scale for
temperatures below 20 K, for higher temperatures it shows a surprisingly sharp
drop into the nanoseconds range. The decrease cannot be explained through
inelastic scattering with phonons, and may be related with elastic scattering
due to phonon-mediated fluctuations of the hyperfine interaction.

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The categories of this paper are: eess
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
14
The categories of this paper are: math-ph
28
The categories of this paper are: alg-geom
33
The categories of this paper are: plasm-ph
6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci