Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Measurement in Electric Circuit   We study fluctuations of electric current in a quantum resistor and derive a
general quantum-mechanical formula for the distribution of transmitted charge.
For that we introduce a scheme of current measurement that involves a spin
$1/2$ coupled to the current so that it precesses at the rate proportional to
the current. Our approach allows the study of charge transfer without breaking
the circuit. We analyze a single channel conductor and derive electron counting
statistics for arbitrary relation between temperature and voltage. For a
perfectly transmitting channel the counting distribution is gaussian, both for
zero-point fluctuations and at finite temperature. At constant voltage and low
temperature the distribution is binomial, i.e., it arises from Bernoulli
statistics.

18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
14
The categories of this paper are: math-ph