Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dispersive readout: Universal theory beyond the rotating-wave
  approximation   We present a unified picture of dispersive readout of quantum systems in and
out of equilibrium. A cornerstone of the approach is the backaction of the
measured system to the cavity obtained with non-equilibrium linear-response
theory. It provides the dispersive shift of the cavity frequency in terms of a
system susceptibility. It turns out that already effortless computations of the
susceptibility allow one to generalize former results beyond a rotating-wave
approximation. Examples are the readout of detuned qubits and thermally excited
multi-level systems. For ac-driven quantum systems, we identify the relevant
Fourier component of the susceptibility and introduce a computational scheme
based on Floquet theory. The usefulness is demonstrated for two-tone
spectroscopy and interference effects in driven two-level systems. This reveals
that dispersive readout does not necessarily measure excitation probabilities.

12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
2
The categories of this paper are: math
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th