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Lecture VII. The Theory of Polarization ch. 14 – part 5 “Notes” . Statistical Models in Optical Communications. Vector algebra in Dirac notation. Vector algebra in Dirac notation. Column:. Row:. Outer Product:. Inner Product:. Coherency matrix .
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Lecture VII • The Theory of Polarization • ch. 14 – part 5 “Notes” Statistical Models in Optical Communications
Vector algebra in Dirac notation Column: Row: OuterProduct: InnerProduct: Coherency matrix
Math background - square bra-ket notation for column and row vectors (I) A “bra” is a row - (the complex transpose of the corresponding ket) A “ket” is a column A “bra-ket” is an inner product
Math background - square bra-ket notation for column and row vectors (II) A “ket-bra” is an outer product Unit vectors
Math background - square bra-ket notation for column and row vectors (III)
Introduction to polarization (I) Z-propagating beam For a monochromatic beam the corresponding real vector field is Jones polarization vector • The state of polarization may be described in terms of this ellipse as follows: • The orientation in space of the plane of the ellipse • The orientation of the ellipse in the plane, • its shape and the sense in which it is described • The size of the ellipse • The absolute temporal phase
Introduction to polarization (II) a b Absolute amplitudes and absolute phases are of secondary interest, just the amplitude ratio and the phase difference counts. Hence the relevant information is embedded in the phasors ratio: Change of basis to e.g. to circular – corresponds to bilinear transformation in the complex plane.
The Coherency Matrix Jones vector E E MUTUAL INTENSITIES INTENSITIES Coherency matrix (D=2) (optical polarization theory) Correlation/covariance matrix (statistics) Density matrix (quantum mechanics) Coherency matrix E E E
The degree of polarization (I) correlation coeff.
phasor of x-pol. phasor of y-pol. SOP descriptions Polarization ellipse Poincare sphere cc circ. pol. 135lin-pol. y-pol. ellipt. pol. Jones polarization vector 45lin-pol. x-pol. ccc circ. pol.
The four Stokes parameters Total power SAME SOP Power imbalance Interferometric terms many one Jones vector one one
Coherency matrixStokes parameters (D=2) Stokes parameters …in terms of coherency matrix Jones vector Coherency matrix in terms of Jones vector elements
The Poincare sphere radius