Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Photon spin operator and Pauli matrix   Any polarization vector of a plane wave can be decomposed into a pair of
mutually orthogonal base vectors, known as a polarization basis. Regarding this
decomposition as a quasi-unitary transformation from a three-component vector
to a corresponding two-component spinor, one is led to a representation
formalism for the photon spin. The spin operator $\hat{\boldsymbol \gamma}$
defined on the space of unit spinors, referred to as the Jones space, has only
component along the wave vector and is represented by one of the Pauli matrices
in the commonly used polarization basis. It is deformed by the quasi-unitary
transformation from the spin operator that is defined on the space of unit
polarization vectors, referred to as the Pancharatnam space. On the basis of
this theory, it is shown that the Cartesian components of spin operator
$\hat{\boldsymbol \gamma}$ are mutually commutative and the spin angular
momentum in units of $\hbar$ is exactly the component of the Stokes vector
along the wave vector.

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The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: eess
1
The categories of this paper are: cs
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The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-alg
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-th
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The categories of this paper are: math
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The categories of this paper are: adap-org
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The categories of this paper are: gr-qc