Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Improvements of the programmable quantum current generator for better
  traceability of electrical current measurements   A programmable quantum current generator based on the application of Ohm's
law to quantum voltage and resistance standards has demonstrated a realization
of the ampere from the elementary charge with a $10^{-8}$ relative uncertainty
[J. Brun-Picard et al. PRX 6, 041051, 2016]. Here, we report on improvements of
the device leading to a noise reduction of the generated quantized current. The
improved quantum current generator is used to calibrate different ammeters with
lower measurement uncertainties. Besides, measurements of its quantized current
using a calibrated Ultrastable Low-Noise Current Amplifier (ULCA) have shown
that the realizations of the ampere at PTB (Physikalisch-Technische
Bundesanstalt) and LNE (Laboratoire national de m\'{e}trologie et d'essais) in
the range $\pm50$ $\mu$A agreed to -3.7 parts in $10^{7}$ with a combined
standard uncertainty of 3.1 parts in $10^{7}$ (coverage factor
$k_\mathrm{c}=1$).

19
The categories of this paper are: eess
1
The categories of this paper are: cs
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
26
The categories of this paper are: bayes-an