Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Filtering (Quantum Trajectories) for Systems Driven by Fields in
  Single Photon States and Superposition of Coherent States   We derive the stochastic master equations, that is to say, quantum filters,
and master equations for an arbitrary quantum system probed by a
continuous-mode bosonic input field in two types of non-classical states.
Specifically, we consider the cases where the state of the input field is a
superposition or combination of: (1) a continuous-mode single photon wave
packet and vacuum, and (2) any number of continuous-mode coherent states.

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The categories of this paper are: nucl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: mtrl-th
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The categories of this paper are: stat
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-alg
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The categories of this paper are: acc-phys
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The categories of this paper are: nlin
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The categories of this paper are: q-fin
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The categories of this paper are: cond-mat