Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum dot single photon sources with ultra-low multi-photon
  probability   High-quality sources of single photons are of paramount importance for
quantum communication, sensing and metrology. To these ends, resonantly excited
two-level systems based on self-assembled quantum dots have recently generated
widespread interest. Nevertheless, we have recently shown that for resonantly
excited two-level systems, emission of a photon during the presence of the
excitation laser pulse and subsequent re-excitation results in a degradation of
the obtainable single-photon purity. Here, we demonstrate that generating
single photons from self-assembled quantum dots with a scheme based on
two-photon excitation of the biexciton strongly suppresses the re-excitation.
Specifically, the pulse-length dependence of the multi-photon error rate
reveals a quadratic dependence in contrast to the linear dependence of
resonantly excited two-level systems, improving the obtainable multi-photon
error rate by several orders of magnitude for short pulses. We support our
experiments with a new theoretical framework and simulation methodology to
understand few-photon sources.

31
The categories of this paper are: ao-sci
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
29
The categories of this paper are: funct-an