Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Direct Measurement of Quantum Efficiency of Single Photon Emitters in
  Hexagonal Boron Nitride   Single photon emitters in two-dimensional materials are promising candidates
for future generation of quantum photonic technologies. In this work, we
experimentally determine the quantum efficiency (QE) of single photon emitters
(SPE) in few-layer hexagonal boron nitride (hBN). We employ a metal hemisphere
that is attached to the tip of an atomic force microscope to directly measure
the lifetime variation of the SPEs as the tip approaches the hBN. This
technique enables non-destructive, yet direct and absolute measurement of the
QE of SPEs. We find that the emitters exhibit very high QEs approaching $(87
\pm 7)\,\%$ at wavelengths of $\approx\,580\,\mathrm{nm}$, which is amongst the
highest QEs recorded for a solid state single photon emitter.

30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
24
The categories of this paper are: dg-ga
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom