Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum electromagnetic X-waves   We show that two distinct quantum states of the electromagnetic field can be
associated to a classical vector X wave or a propagation-invariant solution of
Maxwell equations. The difference between the two states is of pure quantum
mechanical origin since they are internally entangled and disentangled,
respectively and can be generated by different linear or nonlinear processes.
Detection and generation of Schr\"odinger-cat states comprising two entangled
X-waves and their possible applications are discussed.

35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
2
The categories of this paper are: math
25
The categories of this paper are: patt-sol
5
The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ