Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: An autonomous single-piston engine with a quantum rotor   Pistons are elementary components of a wide variety of thermal engines,
allowing to convert input fuel into rotational motion. Here, we propose a
single-piston engine where the rotational degree of freedom is effectively
realized by the flux of a Josephson loop -- a quantum rotor -- while the
working volume corresponds to the effective length of a superconducting
resonator. Our autonomous design implements a Carnot cycle, relies solely on
standard thermal baths and can be implemented with circuit quantum
electrodynamics. We demonstrate how the engine is able to extract a net
positive work via its built-in synchronicity using a filter cavity as an
effective valve, eliminating the need for external control.

15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
5
The categories of this paper are: gr-qc
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
6
The categories of this paper are: astro-ph