Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Optical circulation in a multimode optomechanical resonator   Optical circulators are important components of modern day communication
technology. With their ability to route photons directionally, these
nonreciprocal elements provide useful functionality in photonic circuits and
offer prospects for fundamental research on information processing. Developing
highly efficient optical circulators thus presents an important challenge, in
particular to realize compact reconfigurable implementations that do not rely
on a magnetic field bias to break reciprocity. We demonstrate optical
circulation based on radiation pressure interactions in an on-chip multimode
optomechanical system. We show that mechanically-mediated optical mode
conversion in a silica microtoroid provides a synthetic gauge bias for light,
which enables a 4-port circulator by exploiting tailored interference between
appropriate light paths. We identify two sideband conditions under which ideal
circulation is approached. This allows to experimentally demonstrate $\sim$10
dB isolation and $<$ 3 dB insertion loss in all relevant channels. We show the
possibility of actively controlling the bandwidth, isolation ratio, noise
performance and circulation direction, enabling ideal opportunities for
reconfigurable integrated nanophotonic circuits.

14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph