Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spontaneous Emission Spectrum in Double Quantum Dot Devices   A double quantum dot device is a tunable two-level system for electronic
energy states. A dc electron current directly measures the rates for elastic
and inelastic transitions between the two levels. For inelastic transitions
energy is exchanged with bosonic degrees of freedom in the environment. The
inelastic transition rates are well described by the Einstein coefficients,
relating absorption with stimulated and spontaneous emission. The most
effectively coupled bosons in the specific environment of our semiconductor
device are acoustic phonons. The experiments demonstrate the importance of
vacuum fluctuations in the environment for little circuits of coherent quantum
devices.

11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
31
The categories of this paper are: ao-sci