Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Band Engineering in Cooper-Pair Box: Dispersive Measurements of Charge
  and Phase   Low-frequency susceptibility of the split Cooper-pair box (SCPB) is
investigated for use in sensitive measurements of external phase or charge.
Depending on the coupling scheme, the box appears as either inductive or
capacitive reactance which depends on external phase and charge. While coupling
to the source-drain phase, we review how the SCPB looks like a tunable
inductance, which property we used to build a novel radio-frequency
electrometer. In the dual mode of operation, that is, while observed at the
gate input, the SCPB looks like a capacitance. We concentrate on discussing the
latter scheme, and we show how to do studies of fast phase fluctuations at a
sensitivity of 1 mrad/$\sqrt{Hz}$ by measuring the input capacitance of the
box.

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The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
30
The categories of this paper are: q-alg
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc