Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Current noise spectrum of a quantum shuttle   We present a method for calculating the full current noise spectrum for the
class of nano-electromechanical systems (NEMS) that can be described by a
Markovian generalized master equation. As a specific example we apply the
method to a quantum shuttle. The noise spectrum of the shuttle has peaks at
integer multiples of the mechanical frequency, which is slightly renormalized.
The renormalization explains a previously observed small deviation of the
shuttle current compared to the expected value given by the product of the
natural mechanical frequency and the electron charge. For a certain parameter
range the quantum shuttle exhibits a coexistence regime, where the charges are
transported by two different mechanisms: shuttling and sequential tunneling. In
our previous studies we showed that characteristic features in the
zero-frequency noise could be quantitatively understood as a slow switching
process between the two current channels, and the present study shows that this
interpretation holds also qualitatively at finite frequency.

2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
26
The categories of this paper are: bayes-an
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys