Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Passive optical gyroscope with double homodyne readout   We present a passive, resonant, single-frequency gyroscope design that
utilises polarisation modes of an optical cavity to readout rotation and
generate a laser frequency discriminant. This design is notable for its
simplicity, requiring no modulation electronics or frequency counters. We
extract both the cavity length signal and rotation signal from two
co-propagating beams with orthogonal polarisations. This readout scheme can be
applied to an optical cavity whose polarisation eigen-modes experience
different phase shifts such as fibre rings; whispering gallery mode resonators;
and folded free-space cavities. We apply this technique to the passive
free-space gyroscope and achieve a bias stability of 0.03 degree/h and a
sensitivity of $5 \times 10^{-8}$ rad/sqHz above 1 Hz, with a cavity of area
400 cm^2 and finesse of 10^4. Below 1 Hz the sensitivity of the gyroscope is
limited by the backscattering in the optical cavity and beam jitter of the
laser beam.

15
The categories of this paper are: nucl-ex
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn