Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A chip-scale oscillation-mode optomechanical inertial sensor near the
  thermodynamical limits   High-precision inertial sensing and gravity sensing are key in navigation,
oil exploration, and earthquake prediction. In contrast to prior accelerometers
using piezoelectric or electronic capacitance readout techniques, optical
readout provides narrow-linewidth high-sensitivity laser detection along with
low-noise resonant optomechanical transduction near the thermodynamical limits.
Here an optomechanical inertial sensor with 8.2micro-g/Hz^1/2 velocity random
walk (VRW) at acquisition rate of 100 Hz and 50.9 micro-g bias instability is
demonstrated, suitable for consumer and industrial grade applications, e.g.,
inertial navigation, inclination sensing, platform stabilization, and/or
wearable device motion detection. Driven into optomechanical
sustained-oscillation, the slot photonic crystal cavity provides
radio-frequency readout of the optically-driven transduction with enhanced 625
microg/Hz sensitivity. Measuring the optomechanically-stiffened oscillation
shift, instead of the optical transmission shift, provides a 220x VRW
enhancement over pre-oscillation mode detection due to the strong
optomechanical transduction. Supported by theory, this inertial sensor operates
2.56x above the thermodynamical limit at small integration times, with 43-dB
dynamic range, in a solid-state room-temperature readout architecture.

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The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
2
The categories of this paper are: math
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
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The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
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The categories of this paper are: quant-ph
9
The categories of this paper are: nlin
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The categories of this paper are: math-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: stat
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The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga