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Is stokes vector can be a quantum state?

  1. Feb 29, 2012 #1
    Is a stokes four-vector like (1 1 0 0) being horizontal polarized vector can be treated as a quantum state? If the answer is yes, this state can be used to construct density matrix?
  2. jcsd
  3. Mar 1, 2012 #2
  4. Mar 1, 2012 #3
    But coherency matrix is a 2χ2 matrix, which can be constructed by stokes parameters. The density matrix constructed by stokes vector itself would be a 4χ4 matrix.

    ρ=(1 1 0 0)χ(1 1 0 0)

    If this 4χ4 matrix is a density matrix, how can I measure the degree of polarization of this density matrix?
  5. Mar 1, 2012 #4
    The Stokes vector has 4 real components.

    The coherency matrix is a 2x2 complex matrix built from the unity matrix and the 3 Pauli matricies. That also makes 4 free variables.

    You can easily construct the density matrix from the Stokes vector and vice versa. Born and Wolf's textbook has a pretty good chapter on that.
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